It's tough to work with the fiberglass wing tip unless you have a way to hold its shape to match the wing. So I found a description online that uses a piece(s) of foam, about 1" thick.
First I aligned the aileron with the wing. I used the alignment piece of aluminum angle, and then taped a large angle to the wing and aileron to hold it in that position, then removed the alignment angle.
Press the foam against the end of the wing tip aluminum skins, so it leaves an impression in the foam. Photo #2 and #3.
