There is a trick I use when binding off cable stitches. My designs usually have cables involved. I discovered quite quickly that if I bind off cable stitches normally, my edge will pucker. There are too many bind off stitches as a cable pulls the stitches closer together. I realized that I needed to bind off these cables 2 at a time with k2tog. I have created a video to illustrate how I do this bind off. It is super easy! Give it a whirl and let me know what you think.
The Ava Messy Bun/Pony Tail hat uses this technique to create a smooth edge for the brim.