Drybrushing is fairly simple in concept, but takes a bit to get used to. Get a bit of paint on your brush, then wipe off the paint against a foam pad or piece of tissue, leaving just the "residue" of the paint behind. Basically, you're drying off the brush without removing the paint. The bristles should have no sheen to them, but should still be silver. Then, brush very lightly across the raised surfaces of the cockpit controls. This will leave a small amount of paint behind on just the raised surfaces. I would recommend practicing before trying it, as if done wrong, your entire control surface will be silver. Hope this helps a bit.
demono69