I have finally selected all of my fabric. I am using mostly hand dyed fabric with the red being commercial. going to start on clue one today. I would like to make my units larger than called for so that I can trim them down. How much extra do you allow to do this. I was thinking a 1/4" meaning if the unit size was 4", I would cut it at 4-1/4" and trim it back to 4"