I don't care what I do, I never get an exact measurement. Apparently, I can't even sew a straight line! How crazy is that? I've made over 50 quilts and am still struggling with this. I've read a zillion articles, looked at a bazillion websites, and tried my best. So, don't feel alone with this problem. So far, my best new trick is to use Mary Ellen's (I use a tone of this stuff) and spray it on the fabric before cutting out the shapes, make them a little bigger and cut them down to size like others suggest, and spray it on after stitching the patches together. If I don't "cut big and trim down" the patches never measure what they should no matter how carefully I measure and sew. And even then, the blocks don't always come out right size. I've come to accept my flaws and not fret over things not being perfect.