I have only been quilting a year after retiring and started the mystery quilt with McCall's Quilting. Got to part 3 yesterday and found that I was suppose to draw lines diagonally on the little squares to sew them to the big block but I kept thinking there had to be an easier way (now if this trick has already been shared, I have never seen it) so I pinned the blocks on and then put a piece of painter's tape on the bed of the sewing machine with the edge of the tape measured right down from the needle. Then, I began sewing from the diagonal corner to the other corner, keeping it lined up with the painter's tape. It worked perfectly, check out the three pictures. If someone already came up with this, thank you, if not I just discovered it. I got all 80 corners done perfectly!!! Here are the pictures.