Full details (and an example) here: [link]
There's two black/white badge commissions up for grabs -- one goes to the best entry, and the other one goes to a random entry. (i.e. everyone has a chance to win! You can even submit multiple entries!)
If you're looking for a quick way to enter, just grab this blank and have at it: [link]
Better hurry: It's only going on until the 31st, which isn't that far off! Submit something today!