Does it have to be that size? Here is a tutorial for a cute one, but it's wider. You could just leave out one strip of coins and that would make it smaller.
http://www.modabakeshop.com/2009/02/...aby-quilt.html
It uses 2 charm packs so there is less cutting, too which would save you time. Providing you have a couple charm packs laying around. (I have like, 15, I think... no, I don't have a problem...)