I also label each block by row and column after I have them laid out the way I want. If you are like me and not a pinner, remember to put the label on each block in the same corner (i.e. top left corner). I use that as a guide so I know which raw edge is going to be sewn to the last block. It is very easy to turn the block when you put it on your sewing machine (esp. the first 2 blocks of each row) & sew the wrong side.