20 Game-Changing Knit Sewing Tips in Under 10 Minutes

Sewing with knits can feel intimidating. Maybe you've had wavy seams or skipped stitches or neckbands that just won't lay flat. In less than 10 minutes I'll show you 20 essential tips that will transform the way you sew with knits. Just like that. First, let's talk fabric. There are a few things to look for when you're shopping for knit fabric that'll make all the difference. Check if your pattern calls for two-way or four-way stretch. Some knit fabrics actually only stretch across, not up and down. If you're sewing something fitted, like a pair of leggings, that vertical stretch is super important. At least if you want to be able to sit down. Oh, and here's a hint. Fabrics that have lycra or spandex in them typically have four-way stretch. In addition to stretch, another thing to look for is recovery. Recovery means that the fabric snaps back into shape after it's stretched. The more fitted your pattern is, the more you need recovery to keep your finished project from looking all misshapen and stretched out. Again, a bit of lycra or spandex will really help here. Here's another tip that a lot of beginners don't know. There's one type of knit that you can actually sew just like a woven, and even use it for patterns that call for woven fabrics. That fabric is ponte di roma. Ponte is a heavy double knit that you can use for jackets, pants, skirts, anything that needs a bottom weight fabric. Just sew it like you would a heavy woven. It's a great introduction to sewing knits because it's so stable and it's really easy to sew. And it's comfy to wear too. Whatever fabric you buy, do not forget to pre-wash. Knit fabrics can definitely shrink, stretch, and change when they're washed, so you want to make sure those changes happen before you cut into them. Now let's talk tools. One thing that Haley and I are always repeating on our podcast is that whenever you're struggling with something in sewing, it always comes down to one of only two things. The technique you're using or the tools you're using. And when it comes to sewing knits, there are a few tools that'll make the job a whole lot easier. And I'm not talking about expensive machines you need to invest in like a serger. You can use these no matter what machine you have. First, get a walking foot. It feeds both layers of fabric evenly, preventing that annoying rippling effect you might have experienced. If you've never used one before, don't worry. They're really simple to attach to your machine. You'll also want to use the right needle, either a ballpoint or jersey needle. These needles have slightly rounded tips that slip between the fabric fibers instead of piercing through them. This prevents those tiny holes that can lead to runs in your knit fabric. Another really useful needle is the twin needle. It creates two parallel rows of stitching that stretch. It's a great choice for sewing hems or necklines. Another inexpensive tool that's invaluable when sewing knits are fabric clips like Wonder Clips. These little guys hold your pieces together without the need for pins. They're perfect for knits because they won't damage the fabric and there's no chance of sewing over them if you're using a serger. Okay, we've talked about fabric and you've got some handy tools, so let's talk about cutting. The most important thing when cutting knits is to make sure that the direction of greatest stretch goes around your body. Remember we talked about two-way and four-way stretch earlier? Usually the stretch will be much greater in the horizontal direction, so make sure your pieces are facing the right way. And when you're cutting pieces out, I like to cut my notches as little mountains instead of little valleys. The seam allowances on knit patterns are usually only 3 eighths inch and sometimes they're less, so that way there's no danger of accidentally cutting too far into the seam. The next thing I want you to think about is stabilizing your seams. So what does that mean? Basically, there's a tendency for knit fabric to stretch out as it's sewn. This can result in your finished garment looking too big, being stretched out in certain areas, or just having those funky wavy seams. The fabric itself has a lot to do with this, but there are some things you can do to avoid the problem. It's called stabilizing and it's pretty easy. All you do is sew something into your seam to help support it and give it a little bit of extra recovery. One way to do this is with clear elastic, knit stay tape, or even strips of knit interfacing. Just sew it right into any seams that are prone to getting stretched out or distorted, and everything is going to look a whole lot better. Another thing I like to do is sew strips of mesh into my seams if I'm using a sweater knit with big stitches. This not only gives it a bit more stability, but it also prevents any holes from forming in my seams. That can sometimes happen with bulky or lacy sweater knits. One thing I find super helpful is wonder tape. It's a self-adhesive tape that dissolves later in the wash. I almost always use it to hold hems in place when I'm sewing knits. Not only does it keep the hem temporarily glued down, it also stabilizes so your hem doesn't stretch out as you sew. You might be wondering, do I need to sew stabilizer into all my seams when I sew knits? Not at all. It's really only important in the areas that get stretched out. I almost always use it in the shoulders of knit garments, so if you use it nowhere else, I think you should at least use it there. Then play around and see where else it might help. Okay, now let's talk about stitching your garment together. If you don't have a serger, that's no problem. You can use the zigzag or the lightning stitch on your regular sewing machine. Those stitches give you enough stretch for most knit projects. Even if you do have a serger, you can use these stitches for areas a serger can't tackle, like hems. Speaking of knit hems, if you want to learn more about techniques for hemming knits, we're running a skills workshop in April to help you build up that skill and learn some new techniques. So if you're interested, it's free for Seamwork members, so I'll link to more information below. Now back to stitching with a zigzag or lightning stitch. Always test your stitches on some scraps of fabric to make sure there's enough stretch. Stretch your test seam as far as it'll go and check for any ripping or popping of stitches. If you find your seams are popping, that just means you need to adjust the length and width of your stitches. Play around until the stretch matches better with your fabric. A longer, wider zigzag will give you more stretch. Make sure you're not stretching your fabric as you sew. Support the fabric as you feed it through, and don't allow it to stretch out as it goes through the machine. And definitely don't pull it. I talked about the walking foot earlier, which really helps keep your fabric from stretching out. Another thing you can do is lower your presser foot pressure. This also seriously helps keep your fabric from getting pulled while you sew. You can use something called wooly nylon thread to create seams that are both soft and extra stretchy. It's a special thread with a nice texture and lots of elasticity. Here's how to use it. If you're using a serger, you can use it in the loopers of your machine. If you're using a regular straight stitch machine, use it in the bobbin only. Your seams will feel less irritating against your skin and will be a little bit more stretchy. One area people often struggle with is neckbands. Sometimes you need to change the length of a neckband to get it fit properly without any weird gaping. For that reason, always baste your neckband in place to check the fit before you sew it. Then don't be afraid to make adjustments if you find the band isn't the right size. If you're ready to take your knit sewing to the next level and want to explore using a serger, watch this video next where I show you everything you need to know about serger sewing, including some surprising secrets that will make your knit projects look absolutely professional.