I would straighten/square up the sides of your strips to make them straight. The easiest way is to get some string. Safety pin it to the carpet, stretch it out just longer than the strips. Slide the edge of the strips under the string and mark along the string line. Then straighten up the ends the same way once they are all sewn together. In this pattern, trimming a little here or there is not going to matter. Your border pieces (if any) will just have to be readjusted, but we can help you with that step too :D :D :D