McCall's has one. It's not very good though. It is the pattern I started with, like 5 mei tais ago. The main change I made was to make the shoulder straps really wide, and pleated into the body, so that they would spread the weight out better. Then I cut off the bottom of the body, and replaced it with one really long waist strap, and put bum darts in above the strap. They are pretty simple to make, I'm thinking there must be a few tutorials on blogs somewhere.