RE: BT Bf109E-4
to finish up the detailing on the ailerons i added a simulated metal subsurface and rib stitching. i used BT's plan suggestion for simulating the metal frame by using tissue and dope except for the the underside l.e. of the aileron. for that i used aluminum foil tape mostly to see the difference in that and the tissue.
pic 2: then an application syringe was used to lay down a fine line of white glue to simulate the rib stitching. even though i've been around airplanes for 20 years i've never seen rib stitching up close on the real thing so i was kind of guessing here.
pic 3: with the "stitches" dry, a strip of tissue was doped on top. and the finishing touch was a trim tab added with the same aluminum flashing used before.