I took a class with Harriet Hargrave, and she recommends practicing with paper & pencil, especially if you are trying to learn how to do a design like feathers or if you are going to be doing stencilled borders. However, I found that I could place a piece of template plastic over the design, then trace over the design with a dry erase marker until I feel comfortable tracing the design. In this way, you develop muscle memory and better hand/eye coordination. Once you feel comfortable with paper & pencil, then practice with quilt sandwiches. Another Harriet Hargrave tip is to practice on a quilt sandwich for 20 minutes before you start working on your actual quilt to warm up the muscles; never start quilting on your actual quilt cold; always warm up.