You can do one of two things: 1: trim a graduation so it isn't so noticable, meaning ie: go from 3/16" at the top to 1/4" on the bottom. 2: when you do your 1st border strip, do the same thing but in reverse, have the smaller width at the top and the wider at the bottom. Clear as mud right? I hope this helps. When I first started quilting, baby panels were the rage and none of them were straight...this worked quite nicely.