I tried this one:
http://www.allcrafts.net/f.asp?url=w...03/PD00172.pdf
I sewed the batting on the back of the front fabric. Then put the 2 tops together and left about 2inches open. Then flipped it inside out and sewed the 2inches shut. I think that's how this one was done! I also used Velcro instead of snaps.