drafting, template making and accurate cutting. Accurate cutting in general I have had to learn on my own. squaring up a block, also had to learn on my own, not taught in my first quilt class. Accurate measuring and how to use the various lines on a ruler, still don't know what the different lines are for. Accurate piecing, how to make sure you are getting the correct seam allowance. I would say precision is the number one thing not really taught in most classes and is one of the most important thing. I would have almost liked to learn that instead of making my first quilt in which the seam allowances were all over the place. It is something that I have been teaching myself over the last few years