The original source is The Purple Carrot, feel free to give her a visit. And then, find a frame you like (they're always 50% off at Hobby Lobby!) and some metal hooks.
I cut the back off with a craft knife...
Screwed in the metal hooks on the inside of the frame...
And had a frame with hooks.
Since the wall I'm putting this on was sort of the same color as the frame, I taped some scrapbook paper up where I was hanging the frame. Then I mounted it right on top.
Look how pretty. And with keys hanging:
We have more keys than a medieval dungeon master. This was fun and easy!