I cut my binding 2.25 inches and use a 1/4-inch seam allowance. Then when I trim the quilt, I trim 1/2-inch from the seam line. This allows enough batting to fill the binding. Then I flip it to the back, mitre the corners, and hand stitch it down. The edge of my binding usually just covers the stitching line. I like to have the binding show about the same on the front and back. Doesn't always happen, but that's my goal.