This may be the most challenging part of the whole craft. Take the "tails" (the edge of each strip that sticks out from the woven part) and fold it back over the mat. Then, fold and tuck it into the little "pocket" (the space formed by one strip being woven across the other) to provide a finished edge. It is recommend you tuck under half the tails, those tails that were woven under, before flipping the mat over to do the other half.