You need to make slots in the wood and the covering. Generally half of the CA hinge goes in the control surface and the remainder in the stab, fin or wing. I use the Hobbico CA slot machine which is fantastic but not necessary. I install the hinges after the plane is covered. I make a slot that the CA hinge will slide in easily, drill a 3/16" diam hole in the middle of the slot, clear away the side brushing in the hole created by a rotating drill, insert the hinge, and the put a few drops of thin CA in each half of the drilled hole.