I do a lot of PP using strips. I'll figure out how many strips I need and cut them. I clip them together using those black metal paper binder clips w/ a small paper piece with the numbered section of the block clipped in it. I'll write the color name on a paper mock -up of the block & also glue a small piece of the fabric to that section too, so there's no question as to what fabric goes there. I mark an "X" on the wrong side of one end of each strip, so there's no mistake about right and wrong side, later. Then I just remove one strip from each of the clips, that I need for the block I'm constructing. The rest sit in a pile on the far side of my table. I have tried chain piecing on a long strip of fabric, but there's more waste that way. When that block is done, I clip any of the strips back into their group. I might have a couple clips with the same fabric, but cut to different widths. Then it's real important to make sure you have the numbers on each paper that correlates with your mock-up block. If I have lots of strip sets I'm not using for that block, I just lay them out on my ironing board, to keep them from getting wrinkled. I typically don't make lots of blocks that are exactly the same fabrics, usually each block is different.

I mark each row with a number and sew one row at a time. If necessary I will mark each piece in the block. This may take time but there's not much ripping out. I hate ripping out, it wastes sewing time. I've never forgotten the first adage I learnt in second grade, "a stitch in time saves nine".

thats pretty much how i do it too!

Nothing I've tried has worked for me. I always end up with 1 or more blocks out of place. It may or may not be noticeable. The A1, A2, A3, ..., B1, B2, B3 I think has the best chance of working.

I use JoC's method and its works well for me. Whatever you come up with for yourself will be fine, just use the same method for each block and it becomes a habit