You want to bevel only the ailerons and not the TE. Drill the holes for the hinge before you do any beveling. I draw a center line in the aileron and then put a line on the top and bottom of the aileron where you want the bevel to go to. you can then sand the bevel using the lines as your guide.
For example; let's say the LE of the aileron is 1/2" your center line would then be 1/4" on the LE. On top of the aileron LE make a mark 1/4" the full length of the aileron and when you sand that the bevel to both lines, front and top. Do the same for the bottom of the aileron.