I cut 2 1/4 or 2 1/2 inches, bias or straight stitch them together and then start at the bottom right, which is the last place a person sees usually (at least according to the 'experts'!) I sew the usual 1/4 inch, or sometimes more, depending on the thickness of the quilt. I like to have the binding 'filled', rather than 'empty' when flipped and finished, so it is a guess-timation. The trick is to be consistent and to fill the binding and to have enough to cover the machine stitching when the handwork is done on the back. IMHO!
Another tip: When doing the hand sewing, I use the thinner thread (not cheaper, just thinner! like is found not the pre wound bobbins) because I find that my stitches 'sink' into the seam, and never show.