I watched a video by Nancy Zieman awhile back and she angles the cut on the corners by about .5 inch starting not quite at the middle on each side. I tried it and it works. If you start around 4" from the corner, put your ruler right at the very edge, then angle it as you get to the corner so you're in by .5" at the corner only, then cut. You'll still sew at your .25 inch or .5 inch....whichever is how you stitch yours. I like sewing a .5 inch for pillows as I then take them to my serger to put a nice stitch along the edge so they don't ravel later on.