I just measure the middle and cut my borders to that measurement....this last time had very little to ease in...the top didn't get as much handling as some do so it made a difference...and if I don't have a pucker somewhere I will have one the back guaranteed....that's just my luck so now I check the back frequently and I rarely rip as my quilts aren't perfect and are supposed to look homemade...I try not to pucker but will live with small ones as an added charm and usually once washed it is a lot less noticeable!