Cut accurately, sew accurately. That's about it. I do cut logs to length - and pile them up in order on an extra 6x24 ruler. I have never squared blocks at all - much less after each round. Cutting strips to length makes that unnecessary. Any wonkiness can be solved with the next piece. My latest ( I do love Log Cabins!) recently won the mini quilt contest. For that one, I paper pieced. On graph paper. The logs are 1/4" wide. Lots of trimming on that baby! Each seam allowance needed to be trimmed to 1/8" to avoid bulk. But it was worth it!