I was going to entitle this post "HOT" tip, but it's really not that at all... it's a "COOL" one. How many times do you finish piecing a block, press it flat and transfer it to your cutting table for that final squaring up only to discover it's anything but square? For me the answer is fairly often. I compensate when joining the blocks together but it's rarely a precise proposition. That is, until, I've learned to just cool it! As eager as I may be to square up those just-finished blocks if I leave them on the ironing board to cool completely before trimming they are, usually, just perfect! So simple, it all comes down to patience. Time spent cooling now is time saved struggling to get the blocks to fit together later. Sew cool!