With Scotch tape or masking tape, cover the rows of stitch holes inside and out, pressing the tape tightly to the hull. The tape keeps epoxy from running out of the holes when the laps are being filled, so be careful when taping to avoid missed holes or sections that might leak. There are several ways to do this; covering each hole with a small piece of tape or using a continuous piece of tape for each row of holes. It's a little easier to put on if you use individual pieces, but easier to remove if you use long strips. To insure that the tape is really stuck, rub over it ( or burnish )with the rounded end of a large dowel or broom handle.