You will need:
1) a shear
2) a bending brake/ finger brake
3) a multi-metal disc sander
4) a bench vise
5) a file
6) a scribe or sharpie
7) 30 minutes
Step 1: Find a scrap to transform; cut to width using the shear
You'll need a piece at least 8" long, and you'll be using the shear to cut it to the width you want your keychain to hang from.
Lay your keychain next to your metal scrap. Make a mark on the metal so you know where to line the shear up; I cut mine to about .5", because that will work nicely with the diameter of my key chain.