I am a new quilter too, less than 3 years, but I was shown to fold (in about half) to the stitching line, then just cover it. If you like your binding "full", then leave more of the edge when you "square up"/ "trim edges" of the quilt. Most of the ladies in my group leave it 1/4 to 1/2 inches wide (front, batting, backing, plus the binding seam). I am sure that the more professional quilters will have a better description. If you are entering a competition with the quilt, then follow their rules exactly, or you will be disqualified.