The reason I haven't explored making these buttons before is that I've always tried to find buttons made from "natural" materials, like wood, shell, deer antler, pewter,... However, even though I try to pick up nice buttons whenever I find them (often at sheep and wool festivals), it can be hard to find just the right buttons for a project. That's why I want to learn more about making customized buttons.
And on the topic of buttons, the DSK project is now complete, except for them, but you'll have to wait a few more days for photos while I see what I can come up with at the workshop. In the meantime, here's how to make an easy buttonhole--it's the method I used for the project and I love the result.
Knit to 2 sts before where you want the buttonhole, k2tog, YO, k2tog. On the return row, k1, p1 into the YO. That's it! How did I miss this until now?
For modified instructions to insert this into k2, p2 ribbing, see here.