I just LOVE LOVE LOVE this pattern from Mama's pocketbook. I printed the pattern out a few days ago and studied it intensely so that I would be able to understand what I was doing. (I'm still a newbie)
I think mine turned out pretty great. I use it to carry my little guy's nappies/diapers and wipes as well. It's a LITTLE too small for his stuff too, but when he is potty trained, it will be all mine!!!!
The outer is made from heavy corduroy type material and the inner from a heavy weight curtain fabric. I didn't use that stuff that makes it stiff (what's it called?) because quite frankly I didn't have the know-how. It only cost me NZ$5 to make since I got the fabric on sale.