The best trick is to first decide how you want it shaped. Some planes hinge the ailerons on the top edge, which requires a different type of bevel than if it is supposed to be hinged on the centerline. If yours (and I suspect it is) supposed to hinge on the center line of the aileron, first draw a straight line down the aileron on the centerline from one end to the other. Next draw a line to represent the extreme back cut on the top and the bottom. Next, using a sanding bar, remove the material between the line from the top to the centerline. Turn the aileron over and remove the material between the bottom line and the centerline. You should end up with a perfect V shaped aileron leading edge. Remove a little material at a time, and stop to check your progress often. Don't oversand it.

Bill, AMA 4720
WACO Brotherhood #1