strange_doings (![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png)
strange_doings) wrote2012-07-25 12:12 am
strange_doings) wrote2012-07-25 12:12 am
Entry tags:
Ten Things Every Costumer Should Know
..how to do.
This is a more detailed version of the "Ten Things" panel that I have presented at cons before. It is by no means a required list, but a suggestion, though most of these techniques and tricks are pretty basic for anyone regularly building their own garments from scratch. Integrating these techniques into their repertoire is how any costumer/cosplayer can take their stuff to the next level, to start building costumes that dazzle and wow, fit and flatter. Because let's face it, we all like to look good. No matter what kind of costume it is, a well-made costume shows. Eyes pop and cameras flash, and you simply feel better when you look your best. These ten areas of sewing knowledge are crucial for anyone making cosplay a long-term hobby and wanting to improve their skills, whether for the satisfaction or the attention.
The List
1. Press your seams (using an iron to sew)
Pressing seams open, or just pressing them flat, makes a garment look better and hang right, and helps with linings. Irons are not just for getting wrinkles out, they are important to sewing. Press the seams as you go, and don't wait until the entire thing is assembled in case it makes it harder to get to a certain seam. I tend to press the side and shoulder seams of any garment first, all at the same time, so that when I'm putting on collars or attaching linings, everything already hangs right and looks smooth. Also press hems (before or after sewing), press trim, use the iron to make your own trim (bias tape), press collars. When following a pattern, collars, lapels, and facings usually have the instructions written right there to press, but not always. Topstitching is not a substitute for pressing!
2. Stitch in the ditch
This is an important method not only for collar construction, but putting types of trim, large and small, on edges so as not to show a stitch line. Sometimes it doesn't matter, but if you don't want to show a stitch on top of the bias trim, or the armhole binding or cuff or whatever, stitch in the ditch.
You may or may not find the instructions how to do this in a pattern for collars. It's difficult to explain without photos, but here's a quick and dirty: your collar is usually two pieces sewn front to back, right? You'll sew half the collar onto the body of the garment, usually the back half, using a normal right-side-to-right-side stitch. Then flip the collar so that the inside sandwiches over the stitch you just made. Fold or tuck the seam allowance to the inside and then pin it down so that the folded edge overlaps the stitch line juuuuuuust a little bit extra. Like, a needle's width, 1/8" or so. Then, flip the whole thing over and stitch right on top of the previous seam, or, the "ditch" formed when you pull the two pieces of fabric apart to see the seam. If you do it right, you'll catch the folded edge underneath in your stitch, while the stitch-line on the top is more or less hidden in that place where the collar meets the body.
3. Mitered corners
It's not necessary but learning to miter the corners of bias tape and other trims - and mitering corners in general - adds to the neat, polished look of a garment. Easy for anyone who understands a 90 degree angle and can pin their trim nicely, it may take looking up some youtube tutorials or sewing encyclopedias for beginners to pick up. What it gives you is a clean, diagonal seam at the corners of your trim so you don't have to fiddle around with huge, messy origami-fabric-folds that don't stay pinned nice and slide around and generally look clunky. Considering how many anime/manga costume designs have thin bands of colored trim that are very easily done with a little bias tape, mitering the corners of said tape becomes a must for cosplayers to know about. This technique extends to sewing square or angled edges on all kinds of costumes - boxy necklines, random openings or dagged edges, and quilted or pieced decorations.
4. Proper lining method and tricks
There are a number of ways to line a garment, though most of the difference is in which seams get sewn in which order, and as a result, where visible stitches are wanted or allowed in order to close up the garment. Many basic patterns will teach how to line for that specific garment, but there are a few universal tricks that are good to know so you can decide which one is best used on the costume. Because let's face it, we don't always want to "invisibly hand stitch" the hems of our lined garments.
- inner sleeve topstitch. I learned this from a Civil War pattern. If your pattern method allows, and you intend to connect the sleeves to the sleeve linings via regular machine stitch and NOT hand-stitching (ugh), a good way to keep it clean is to topstitch the seam allowance toward the lining. There will be a little stitch line on the inside of the sleeve, but your outer sleeve cuff will be stitch-free and nice and clean.
- let the garment hang out for a couple of days to eliminate sag. No, really. Sometimes we don't always choose the correct fabrics for our linings, and if we just go and sew the lining to the outer shell without waiting, the lining - or shell - could sag or pucker where the two are joined. Nobody wants a saggy lining. Pin the two together, before or after attaching collars, hoods, or sleeves, matching the top and front-side edges. Then, hang it up and walk away. Overnight is sometimes enough if you're not expecting sag; a day or two at most will do it. You'll see where the pins are pulling or puckering, and can re-pin it based on that.
- Sewing with two different color threads is acceptable. Yes. Go ahead. It makes sense, doesn't it? If the lining is a different color from the outer shell, of course you would use the correct color thread for top and bottom based on how it's being put together. Mainly, this is a quick and easy way to cover your butt in case your machine's tension is off or the fabric pulls on the seams in unexpected ways.
- Pillowcasing. This is the most rudimentary lining method, and the foundation of other linings. Sew around the edges, leave a small hole for turning, pull it inside out, close the hole. Fantastic for making double-thickness sashes, belts/obis, shawls, and anything else that doesn't have lots of extra wacky shapes like, you know, sleeves. The real trick, though, is to know how to close up that hole. Pillows often have a topstitch, it's easy to see because the fabric has been pinched and the stitch runs right on top of it. But if your garment piece has nowhere to hide such an obvious blip, it's better to learn to hand-sew a quick slip-stitch.
5. Facings
A facing is a piece of fabric sewn to the edge of a garment in lieu of a lining, to give an unlined garment a cleaner edge finish than a folded-over hem. Facings are very common on the front edge of a button-up shirt or a coat, but they can also be found on arm holes (often for vests), collars (when there is no stand-up collar or lapel, just a flat collar edge), and occasionally even the bottom edge of some blazers. The general technique can be learned by following any pattern for a button-up shirt, it even gives you the weird-shaped pieces that become the facing so you can see how this piece fits into the finished garment. Once learned, it becomes easier to trace the edges of arm holes or collars to make specialized facings. The shaping of the facing is the only hard part - after that, sewing it on is a breeze and often, much easier than trying to hem a curve.
Facings usually have to be at least pressed to the inside, if not topstitched, but that can be decided based on how the garment is supposed to look when finished, whether you want a visible topstitch or not. Facings are good for anything where just a half inch raw hem won't look nice, or anything that needs a tiny bit of an extra layer without a full lining. It makes a much cleaner edge on the front, neck, or arm hole of a garment than folding a hem.
6. Shaping garments by adding gores, godettes, gussets, darts, and seam flare
That's probably a lot to get through in just one blog, and many places both online and in sewing books have specific tutorials and instructions for how to add these things into a garment, where to use them and why. What I want is merely for costumers/cosplayers to know that these techniques exist, and may very well be what you're looking for in order to shape that special costume just right.
Gores, godettes, and gussets are terms for separate pieces of fabric that are sewn into certain seams in garments in order to change their shape. For example, to add a lot of volume and flare to a skirt, dress, or trenchcoat, you would sew triangular gores into the side and back seams. Gussets are usually used to create specially-shaped sleeves or crotch seams (such as skin-tight leggings). Once you see one of these sneaky pieces of fabric in play, you may suddenly see all the potential for using them.
Darts are the opposite - they are extra seams sewn into the piece of fabric to create fantastic new shapes. You often see them at waistlines and bustlines, particularly for women's garments, but men also have them in suit coats and blazers. Following a pattern will teach how darts are sewn, but what's important to a learning costumer is figuring out when it would be okay to eliminate darts, when you will need to add some that the pattern doesn't have, and when to add them to your own drafted patterns or draped pieces. Even if a costume's design doesn't show darts, they are often the best or even only way to get extremely fitted blouses and jackets over shapely chests and hips.
Finally, shaping the seams in a garment will change its overall shape. It's important to learn where in a garment it's okay to reshape a seam, and where it will give you the look you want, versus where it will totally screw up the shape. A good example of shaping seam is a center back seam: it allows you to curve a garment inward to a narrow waist and then flare back out for flowing dresses and trenchcoats. It's also very useful for vents in coats.
7. Proper applique techniques
When it comes to appliqueing one piece of fabric onto another, there's a lot of right ways and a few wrong ways. Simply leaving your edges raw and unfinished is a wrong way. It makes your costume look shabby, and increases the possibility of the applique falling off eventually. When it comes to applique, you want it to be secure, and you want it to look nice and neat. Iron-on products and glues are good for positioning the applique where you want it, but they're not permanent.
Absolutely anyone with a sewing machine can do a basic applique stitch. It's called satin stitch, but it has nothing to do with satin. It's really a very narrow zig-zag stitch, sewn around the entire edge of the applique. Fancier machines have a satin stitch setting, but even the most simple machine with a zig-zag setting you can control will work fine. Set the zig-zag width however wide you want it - it should be wide enough to catch the edge of the applique securely - but at a length just barely above zero and not quite 1. The stitch should still move, but it will make a very solid-looking zig-zag stitch.
Folding over the edge of the applique to do an edge stitch only really works on straight-edged geometric shapes. Curves need to be clipped in order to be folded under, and often leave you with jagged-looking edges if the curves are too sharp and the applique is too small or complex to be pinned and held that way. Satin-stitching takes less work and less braining, and will leave a much neater appearance. It can even be used for special effects, like using a contrasting-color thread to make a colored border around the applique.
8. Rolled hems
The most basic hem is just folding the edge under and stitching it down. But that often leaves loose threads and leads to fallen hems if the fabric frays to the stitching. A better way is to do a rolled hem. It requires budgeting a little extra into the seam allowance when cutting (usually 1/4" to 1/2" at the most), but the finished result is a very neat hem that safely hides all your raw edges and loose threads, and protects them from fraying. Just as it sounds, a rolled hem is a hem that is folded under twice. Usually, you fold under the extra quarter to half an inch, and then fold again along your actual hem line, and then edge stitch on top of that first fold. It helps to press the extra fold so that it stays down while you're trying to sew. Rolled hems are so easy and basic and really add to the neat, clean finish of any un-lined garment.
9. Alternate methods for attaching trim, and types of trim.
There's a lot to say about trim that I'm not going to say here. Again, I simply want costumers and cosplayers to know that there are many different types of trim, some of which may be more or less appropriate to the intended costume, and multiple methods of attaching said trim depending on whether or not visible stitches and seams are wanted. The information is out there on the interwebs to be googled, so take the time first to examine the costume's design and determine what you want out of the finished product.
I personally like hiding my stitches as often as possible. Even with bias tape, I'm not satisfied simply sandwiching a little extra-wide-double-fold over an edge and topstitching the whole thing down. Though that is a legitimate way of attaching bias tape. I like to use a stitch in the ditch method, myself. And by the way, making your own bias tape is pretty easy. It's a little more time consuming than picking up a package, but if you need a very specific color that they don't produce commercially, or you want your bias-taped edge to be 3/8" or 5/8" or 3/4" and that one-size-only bias tape won't cut it, making it yourself is the way to go. It means learning about the bias of fabric - the diagonal grain to the selvage - and cutting strips of fabric that need to be pressed to make the folds for the tape.
10. Flat-felled and French seams
Sometimes, whether because of the way a garment has to go together or for reasons of historical accuracy, finishing seams with a serger or zig-zag is not enough. Granted, everyone should finish their seams in some fashion. When I was still a beginner more than 12 years ago, I didn't know about this, and now it's too late to go back and zig-zag the seams of some of my first costumes. They're falling apart from fraying. So, first of all, finish your seams. But now that I've said that, I want to mention that it would be a great idea for all costumers/cosplayers to learn alternate methods of seam-finishing, like flat-felled and French seams.
French seams are great for skirts - especially petticoat and undergarment skirts! - where there may be a lot of very long seams that need to be very secure. It means sewing each seam twice: first, you place the pieces WRONG sides together and sew a very narrow seam, like 1/4", and then flip it around (press it!) and pin it again RIGHT sides together, and sew the seam again. It means you're folding your raw edges inside and sewing them into a little tiny pocket of seam. If using a pattern's standard 5/8" seam allowance, you don't even have to budget extra for this type of seam.
Flat-felled seams are a little trickier, and I find there are several ways to do them depending on which sewing book or pattern you're reading. The basic gist of a flat-fell is that upon sewing the seam, you trim one half of your seam allowance and then fold the other half so that it covers all the raw edges, and sew that down. Often, this kind of seam means visible top-stitching on the outside of the garment, so it may not be appropriate for all seams. The outside leg seam on any commercial pair of jeans is a flat-felled seam. Men's dress shirts often have flat-felled sleeve seams. I have also seen other ways to make the same kind of look as a flat-felled seam but through different folding and sewing, but it always ends with a visible top-stitch.
So there you have it. Go forth and learn and be beautiful!
This is a more detailed version of the "Ten Things" panel that I have presented at cons before. It is by no means a required list, but a suggestion, though most of these techniques and tricks are pretty basic for anyone regularly building their own garments from scratch. Integrating these techniques into their repertoire is how any costumer/cosplayer can take their stuff to the next level, to start building costumes that dazzle and wow, fit and flatter. Because let's face it, we all like to look good. No matter what kind of costume it is, a well-made costume shows. Eyes pop and cameras flash, and you simply feel better when you look your best. These ten areas of sewing knowledge are crucial for anyone making cosplay a long-term hobby and wanting to improve their skills, whether for the satisfaction or the attention.
The List
1. Press your seams (using an iron to sew)
Pressing seams open, or just pressing them flat, makes a garment look better and hang right, and helps with linings. Irons are not just for getting wrinkles out, they are important to sewing. Press the seams as you go, and don't wait until the entire thing is assembled in case it makes it harder to get to a certain seam. I tend to press the side and shoulder seams of any garment first, all at the same time, so that when I'm putting on collars or attaching linings, everything already hangs right and looks smooth. Also press hems (before or after sewing), press trim, use the iron to make your own trim (bias tape), press collars. When following a pattern, collars, lapels, and facings usually have the instructions written right there to press, but not always. Topstitching is not a substitute for pressing!
2. Stitch in the ditch
This is an important method not only for collar construction, but putting types of trim, large and small, on edges so as not to show a stitch line. Sometimes it doesn't matter, but if you don't want to show a stitch on top of the bias trim, or the armhole binding or cuff or whatever, stitch in the ditch.
You may or may not find the instructions how to do this in a pattern for collars. It's difficult to explain without photos, but here's a quick and dirty: your collar is usually two pieces sewn front to back, right? You'll sew half the collar onto the body of the garment, usually the back half, using a normal right-side-to-right-side stitch. Then flip the collar so that the inside sandwiches over the stitch you just made. Fold or tuck the seam allowance to the inside and then pin it down so that the folded edge overlaps the stitch line juuuuuuust a little bit extra. Like, a needle's width, 1/8" or so. Then, flip the whole thing over and stitch right on top of the previous seam, or, the "ditch" formed when you pull the two pieces of fabric apart to see the seam. If you do it right, you'll catch the folded edge underneath in your stitch, while the stitch-line on the top is more or less hidden in that place where the collar meets the body.
3. Mitered corners
It's not necessary but learning to miter the corners of bias tape and other trims - and mitering corners in general - adds to the neat, polished look of a garment. Easy for anyone who understands a 90 degree angle and can pin their trim nicely, it may take looking up some youtube tutorials or sewing encyclopedias for beginners to pick up. What it gives you is a clean, diagonal seam at the corners of your trim so you don't have to fiddle around with huge, messy origami-fabric-folds that don't stay pinned nice and slide around and generally look clunky. Considering how many anime/manga costume designs have thin bands of colored trim that are very easily done with a little bias tape, mitering the corners of said tape becomes a must for cosplayers to know about. This technique extends to sewing square or angled edges on all kinds of costumes - boxy necklines, random openings or dagged edges, and quilted or pieced decorations.
4. Proper lining method and tricks
There are a number of ways to line a garment, though most of the difference is in which seams get sewn in which order, and as a result, where visible stitches are wanted or allowed in order to close up the garment. Many basic patterns will teach how to line for that specific garment, but there are a few universal tricks that are good to know so you can decide which one is best used on the costume. Because let's face it, we don't always want to "invisibly hand stitch" the hems of our lined garments.
- inner sleeve topstitch. I learned this from a Civil War pattern. If your pattern method allows, and you intend to connect the sleeves to the sleeve linings via regular machine stitch and NOT hand-stitching (ugh), a good way to keep it clean is to topstitch the seam allowance toward the lining. There will be a little stitch line on the inside of the sleeve, but your outer sleeve cuff will be stitch-free and nice and clean.
- let the garment hang out for a couple of days to eliminate sag. No, really. Sometimes we don't always choose the correct fabrics for our linings, and if we just go and sew the lining to the outer shell without waiting, the lining - or shell - could sag or pucker where the two are joined. Nobody wants a saggy lining. Pin the two together, before or after attaching collars, hoods, or sleeves, matching the top and front-side edges. Then, hang it up and walk away. Overnight is sometimes enough if you're not expecting sag; a day or two at most will do it. You'll see where the pins are pulling or puckering, and can re-pin it based on that.
- Sewing with two different color threads is acceptable. Yes. Go ahead. It makes sense, doesn't it? If the lining is a different color from the outer shell, of course you would use the correct color thread for top and bottom based on how it's being put together. Mainly, this is a quick and easy way to cover your butt in case your machine's tension is off or the fabric pulls on the seams in unexpected ways.
- Pillowcasing. This is the most rudimentary lining method, and the foundation of other linings. Sew around the edges, leave a small hole for turning, pull it inside out, close the hole. Fantastic for making double-thickness sashes, belts/obis, shawls, and anything else that doesn't have lots of extra wacky shapes like, you know, sleeves. The real trick, though, is to know how to close up that hole. Pillows often have a topstitch, it's easy to see because the fabric has been pinched and the stitch runs right on top of it. But if your garment piece has nowhere to hide such an obvious blip, it's better to learn to hand-sew a quick slip-stitch.
5. Facings
A facing is a piece of fabric sewn to the edge of a garment in lieu of a lining, to give an unlined garment a cleaner edge finish than a folded-over hem. Facings are very common on the front edge of a button-up shirt or a coat, but they can also be found on arm holes (often for vests), collars (when there is no stand-up collar or lapel, just a flat collar edge), and occasionally even the bottom edge of some blazers. The general technique can be learned by following any pattern for a button-up shirt, it even gives you the weird-shaped pieces that become the facing so you can see how this piece fits into the finished garment. Once learned, it becomes easier to trace the edges of arm holes or collars to make specialized facings. The shaping of the facing is the only hard part - after that, sewing it on is a breeze and often, much easier than trying to hem a curve.
Facings usually have to be at least pressed to the inside, if not topstitched, but that can be decided based on how the garment is supposed to look when finished, whether you want a visible topstitch or not. Facings are good for anything where just a half inch raw hem won't look nice, or anything that needs a tiny bit of an extra layer without a full lining. It makes a much cleaner edge on the front, neck, or arm hole of a garment than folding a hem.
6. Shaping garments by adding gores, godettes, gussets, darts, and seam flare
That's probably a lot to get through in just one blog, and many places both online and in sewing books have specific tutorials and instructions for how to add these things into a garment, where to use them and why. What I want is merely for costumers/cosplayers to know that these techniques exist, and may very well be what you're looking for in order to shape that special costume just right.
Gores, godettes, and gussets are terms for separate pieces of fabric that are sewn into certain seams in garments in order to change their shape. For example, to add a lot of volume and flare to a skirt, dress, or trenchcoat, you would sew triangular gores into the side and back seams. Gussets are usually used to create specially-shaped sleeves or crotch seams (such as skin-tight leggings). Once you see one of these sneaky pieces of fabric in play, you may suddenly see all the potential for using them.
Darts are the opposite - they are extra seams sewn into the piece of fabric to create fantastic new shapes. You often see them at waistlines and bustlines, particularly for women's garments, but men also have them in suit coats and blazers. Following a pattern will teach how darts are sewn, but what's important to a learning costumer is figuring out when it would be okay to eliminate darts, when you will need to add some that the pattern doesn't have, and when to add them to your own drafted patterns or draped pieces. Even if a costume's design doesn't show darts, they are often the best or even only way to get extremely fitted blouses and jackets over shapely chests and hips.
Finally, shaping the seams in a garment will change its overall shape. It's important to learn where in a garment it's okay to reshape a seam, and where it will give you the look you want, versus where it will totally screw up the shape. A good example of shaping seam is a center back seam: it allows you to curve a garment inward to a narrow waist and then flare back out for flowing dresses and trenchcoats. It's also very useful for vents in coats.
7. Proper applique techniques
When it comes to appliqueing one piece of fabric onto another, there's a lot of right ways and a few wrong ways. Simply leaving your edges raw and unfinished is a wrong way. It makes your costume look shabby, and increases the possibility of the applique falling off eventually. When it comes to applique, you want it to be secure, and you want it to look nice and neat. Iron-on products and glues are good for positioning the applique where you want it, but they're not permanent.
Absolutely anyone with a sewing machine can do a basic applique stitch. It's called satin stitch, but it has nothing to do with satin. It's really a very narrow zig-zag stitch, sewn around the entire edge of the applique. Fancier machines have a satin stitch setting, but even the most simple machine with a zig-zag setting you can control will work fine. Set the zig-zag width however wide you want it - it should be wide enough to catch the edge of the applique securely - but at a length just barely above zero and not quite 1. The stitch should still move, but it will make a very solid-looking zig-zag stitch.
Folding over the edge of the applique to do an edge stitch only really works on straight-edged geometric shapes. Curves need to be clipped in order to be folded under, and often leave you with jagged-looking edges if the curves are too sharp and the applique is too small or complex to be pinned and held that way. Satin-stitching takes less work and less braining, and will leave a much neater appearance. It can even be used for special effects, like using a contrasting-color thread to make a colored border around the applique.
8. Rolled hems
The most basic hem is just folding the edge under and stitching it down. But that often leaves loose threads and leads to fallen hems if the fabric frays to the stitching. A better way is to do a rolled hem. It requires budgeting a little extra into the seam allowance when cutting (usually 1/4" to 1/2" at the most), but the finished result is a very neat hem that safely hides all your raw edges and loose threads, and protects them from fraying. Just as it sounds, a rolled hem is a hem that is folded under twice. Usually, you fold under the extra quarter to half an inch, and then fold again along your actual hem line, and then edge stitch on top of that first fold. It helps to press the extra fold so that it stays down while you're trying to sew. Rolled hems are so easy and basic and really add to the neat, clean finish of any un-lined garment.
9. Alternate methods for attaching trim, and types of trim.
There's a lot to say about trim that I'm not going to say here. Again, I simply want costumers and cosplayers to know that there are many different types of trim, some of which may be more or less appropriate to the intended costume, and multiple methods of attaching said trim depending on whether or not visible stitches and seams are wanted. The information is out there on the interwebs to be googled, so take the time first to examine the costume's design and determine what you want out of the finished product.
I personally like hiding my stitches as often as possible. Even with bias tape, I'm not satisfied simply sandwiching a little extra-wide-double-fold over an edge and topstitching the whole thing down. Though that is a legitimate way of attaching bias tape. I like to use a stitch in the ditch method, myself. And by the way, making your own bias tape is pretty easy. It's a little more time consuming than picking up a package, but if you need a very specific color that they don't produce commercially, or you want your bias-taped edge to be 3/8" or 5/8" or 3/4" and that one-size-only bias tape won't cut it, making it yourself is the way to go. It means learning about the bias of fabric - the diagonal grain to the selvage - and cutting strips of fabric that need to be pressed to make the folds for the tape.
10. Flat-felled and French seams
Sometimes, whether because of the way a garment has to go together or for reasons of historical accuracy, finishing seams with a serger or zig-zag is not enough. Granted, everyone should finish their seams in some fashion. When I was still a beginner more than 12 years ago, I didn't know about this, and now it's too late to go back and zig-zag the seams of some of my first costumes. They're falling apart from fraying. So, first of all, finish your seams. But now that I've said that, I want to mention that it would be a great idea for all costumers/cosplayers to learn alternate methods of seam-finishing, like flat-felled and French seams.
French seams are great for skirts - especially petticoat and undergarment skirts! - where there may be a lot of very long seams that need to be very secure. It means sewing each seam twice: first, you place the pieces WRONG sides together and sew a very narrow seam, like 1/4", and then flip it around (press it!) and pin it again RIGHT sides together, and sew the seam again. It means you're folding your raw edges inside and sewing them into a little tiny pocket of seam. If using a pattern's standard 5/8" seam allowance, you don't even have to budget extra for this type of seam.
Flat-felled seams are a little trickier, and I find there are several ways to do them depending on which sewing book or pattern you're reading. The basic gist of a flat-fell is that upon sewing the seam, you trim one half of your seam allowance and then fold the other half so that it covers all the raw edges, and sew that down. Often, this kind of seam means visible top-stitching on the outside of the garment, so it may not be appropriate for all seams. The outside leg seam on any commercial pair of jeans is a flat-felled seam. Men's dress shirts often have flat-felled sleeve seams. I have also seen other ways to make the same kind of look as a flat-felled seam but through different folding and sewing, but it always ends with a visible top-stitch.
So there you have it. Go forth and learn and be beautiful!