From the inside, taper feather the hole. Now place duct tape pulled tight over the outside of the hole. Next cut a piece of 7oz(or whatever med weight you might get)twill the size of the taped home from the inside. Gradually cut pieces a little bigger until you have about 3-4 inches of overlap from the hole to the hull. Should take about 4-6 layers depending on the glass used. Ideally you want it to match the thickness of the hull.
Mix up a bit of fairing filler and cover the tape from the inside. Wet out the layers of glass over it. Cover with wax paper and smooth out with a card or whatever. Once set up. Pull off wax paper and duct tape. Sand outside about 2-4 inches around the filled hole and finish with some fairing filler until smooth. The inside doesn't need any more attention if you done care.
