Elle, That is right, do not sew sashing on the right side of the 13th blocks AND do not sew sashing on the bottom row. After the blocks are sewn together you will sew a skinny 3/4" ( finished 1/4" ) strip to the sides and then the bottom and top! :D
:?: I have question too. It sounds like many of you are sewing a strip to the tris them cutting to size for the scallops, is that right? I printed off a scallop pattern and was going to sew them individually...