1. To make the guide, take a piece of plywood 7 inches wider than the saw's sole and cut a 2-inch strip off the factory edge. The remaining piece is the base. Snap a line on the base 5 inches from the edge you cut, then glue and screw the strip facedown, with the factory edge on the line. Now set your saw's blade ¾ inch deep, put the sole against the guide strip, and trim the base.