The method I have seen in most books is a whip-stitch but I prefer a running stitch that matches or contrasts with the fabric. I poke the needle thru the top binding and the batting but not the back and then back up. It doesn't show on the back. That's just me. I know many prefer the whip-stitch.
Here is the whip-stitch:
http://www.wonderhowto.com/how-to/vi...y-hand-215189/