I also wondered where to place the marking line on the fabric. Over the edge onto the fabric so you might need to trim or right at the very edge of the outer fabric. Then when it comes to the pre-cuts that have the pinked edge, what do you consider the edge for sewing the 1/4"? Simple questions that could make or break it for you when coming out with the correct sized block. I like the patterns that have you cut over sized so you have to go back and trim to the correct size. This way it allievates the problems.