What I do is take the 1st 2 blocks, put them facing together and just pin them, then take the next 2 and pin, add to the top of the pile. They don't have to be pinned neatly, just pinned to stay together, then once at the machine, I'll pin them correctly and sew. I also don't cut between each set of blocks until I'm done sewing so they stay in the same order, then I cut the thread between. I then put them back up on the design wall making sure they're in the correct order and start taking them off once again pinning as I did before. So far I've kept them in order. I know this seems time consuming but so is frogging seams so which would you rather do?