Definitely cut larger, then after all applique is finished & block pressed ( I would wait until all blocks are appliqued then trim them all- some will draw up more than others) when you trim them Do Not trim them to Finished size! Remember you still need seam allowance for joining the blocks, so trim, square up to 17 1/2" . please show us your progress as you proceed, I have been watching this ( book) for sometime.
