I saw a great idea on a quilt show, though can't remember which one. Start with white tulle and something to attach it to. I've used a picture mat and duct taped the tulle to it, but now I use an embroidery hoop cause it's easier and faster, but you have to use the hoop upside down so the tulle lays flat on the stencil. Trace the design onto the tulle with a permanent marker (you can see through the holes in the tulle). Then put the tulle, still attached to mat or hoop, onto the quilt and follow the lines using your chalk pencil. The chalk rubs through the holes and makes an unbroken line for a pattern. Tulle is cheap and you can reuse it. I store mine folded in a plastic sleeve and keep them in a binder. I put the original paper pattern on top the tulle in the sleeve so that I can easily find the pattern I want. It's a pretty good system.