After sewing quite a few Aiden hoodies, I thought I’d share the method I used to sew those tricky corners seams you see at the body and sleeves of this pattern:
To follow my method you’re going to need small, very sharp scissors, pins, basting thread and a needle. Baste the stitching line on all pattern pieces so you can easily determine when to pivot. If you are using a lightweight fabric for your sewing project, using a iron on stabilizer will make your life much easier. But on a heavy jogging fabric, like the one I used, basting the stitching lines is sufficient to achieve sharp corners.
What you’re going to do first is mark the seam allowance on the back of the fabric to find the exact point where the corners intersect. If you want to you can mark the entire seam allowance to have a clear guidance on where to stitch. Do it for both pieces of fabric that are going to be sewn together, not just the top one.
Next you’re going to pin the pieces together at the corner. Just put a pin through the exact corner of the two pieces of fabric (in this case the bleu front bodice and the grey chevron. Since you marked the seamline, it is easy to know just where to place that pin.
Pivot the fabric pieces until the edges line up along the first seam you will be sewing. In this sample, we’re working with stretch fabric, so zigzag stitch the seam. If you work with non-stretch fabric, use your regular straight stitch. I find it best to sew with the corner (as opposed to the “pointed piece”) on top. Remove the pin just before you reach it. On the final stitch make sure that your needle lands in the exact corner where the pin was. With the needle still down in the fabric, lift the presser foot. This is the pivot point.
Now lift your presser foot, take your scissors and cut into that corner at a 45º angle. It is exactly like a welt pocket where you don’t want to cut into the stitching, but instead get as close as possible (barely 2 mm or 1/16″). Just like with a welt pocket, the closer you cut the sharper your corner will be. Just make sure not to cut into the stitching!
Now pivot and turn the fabric so the new seamline is in front of you. Take all of the fabric that’s bunched up and push it to the side and back, match up the seams and start sewing. It may take a minute to pivot and orient your fabric—just take your time! You’ll see a tiny fold right before the needle. Sew right over it. The more you cut into that corner the smaller the fold and the sharper your corner will be. That’s why it is important to cut as closely as possible.
Now all that’s left to do is press your corner. And in case you’re sewing the Aiden hoody, repeat the whole proces for all the other corners on the front & back bodice and sleeves.