goldenthreads makes a really great paper for this...Right now, I only have the 24" rolls in stock, but I sell more of that size because you can have your DH cut into 2-12" rolls..or like me, I have them cut into 4", 6", 8" and 12"!
I have traced printed patterns and I have used plastic stencils, either way it works great...even if you freehand a design...