I used a simple pattern Nezumi World, and read some helpful tips on working with wire over at seafore.com.
I used a 28 gauge wire and a 3.5 metal crochet hook.
Here I am using the tail from the the slip knot to tie around the spring clasp.
It was surprisingly easy. The only tip I have is that it's difficult to undo stitches, so make sure the loop on the needle is a good size before you start the yo process.