I feel your pain:) When I first started quilting I could not get anything to match. I was using the lines on my mat sometimes and using lines on my ruler. The mat had warped and I got it flat again. In the process the lines were distorted! I now use the lines on my ruler and keep the same style/brand of rulers to keep my cutting consistent. My goal is consistent seams usually a scant ¼". Don't give up!