Rick,
John's procedure is correct, particularly for full size aircraft. However, F&M Enterprise (Poly Fiber producer) also offers a polyester fabric for models. Its called Stits Lite. Its much lighter than standard fabric. They have entire system of fabric, adhesive (Poly Tac), fabric sealer (Poly Brush), silver UV coat (Poly Spray), and top coat paint (Poly Tone). The system is MEK based and is arguablely the lightest system available. The fabric shrinks about 12% and is truely biaxial. I did a 33% YMF-5 and am really pleased.
Here's their web address
http://www.stits.com/index.html They also offer a 150 manual and video that's a real gold mine of information. This may be old information, but one never knows.
Good luck