I'm working on the Favorite Things Uptown Coat and it is coming along swimmingly. But I think every jacket is improved with a loop to hang it on a hook. I wanted a sturdy loop, so dug up some nylon cording.
I cut a bias strip 8" long from the lining fabric (because that's how big my scrap was). I folded the bias strip in half around the cording, and using my zipper foot, sewed close to the cording, making sure not to sew through the cording.
Then I slid the bias tube down toward one end of the nylon cord and sewed across the bottom edge of the tube, securing the tube to the cord.
Then I trimmed the seam allowance to about 3/16", give or take.
Then I turned the bias tube right side out by sliding it over itself. The seam where I sewed across the cord was the anchor. You can see in the photo above that I had much more bias tube than cord. This was intentional. Once I sewed the bias tube, I realized it was way too long. So instead of wasting that much cording, I slid the bias tube down to the end of the cord.
Here you can see the corded loop, nicely turned. Because the tube is bias, it stretches a bit as it turns right side out and then relaxes around the cord.
You can also use this technique to make spaghetti straps. Most of the time you will want skinny straps to be corded with something like cotton, and you want to be sure that the cording doesn't show through your fabric.
If you want to make tiny tubes of fabric for applique or other flat applications, you can use my method and slide the tube almost all the way to the end of the cord before you sew the tube to the cord. Then when you turn the tube right side out onto itself, the tube will be hollow and can be ironed flat.
If you skip the step of trimming the seam allowance, you can have a slightly puffy tube of fabric, which is great in some applications (small straps on a doll dress, maybe?).