Check out this warp. It's going to be a red towel with black accents that make squares. Note how uneven the empty dents are spaced in the reed?
I wound the warp with three ends together, and as I put the first set through the reed I counted. 3, 6, 12....24! Great! That's just how many threads I need!
And then I decided it would be a lot easier to just count 1,2,3...etc. and treat each group of three as one. No problem! I finished the first bit of warp threads, made a correction, and continued on.
Halfway into the last group of warp threads I realized something was a miss. I had miscalculated! 24 divided by 3 is eight...not six. Oh dear! Time to re-sley the reed!
In this photo I have about half of the first set of warp threads re-sleyed. The whole fix has been made (including fixing a later error...probably caused from catching pretend marshmallows that my 3 year old was toasting over a pretend fire....hmm. Maybe I shouldn't be trying to count when I'm playing with my kids! :) and I'm working on the threading!