There are MANY ways to do this, and until today I thought I had the perfect method, but I now have a new favourite way!!
As usual, leave a tail before starting to stitch your binding. Stitch as usual right around your quilt, and finish stitching about 12 or so inches from where you started. (Of course, you back stitched at the beginning and end, didn't you?).
Now fold the loose ends so that they just touch about halfway between the beginning and end of the stitching.
Measure HALF the binding width from the finger pressing.
For this quilt that's 1 1/4 inches as the binding is 2 1/2 inches.
Open the binding ends and have right sides together. Turn one slightly so they are 90 degrees to each other and sew together at the 45 degree line.