A community member from Elizabethtown PA writes:
Take a 2 1/2 inch cheap paint brush and cut it down to 1/4 of an inch. Wrap the metal band with plenty of electrical tape so you won?t scratch your paint. It works great for getting the extra wax from the small cracks on your car.
This definitely works. An old, soft bristle toothbrush works great, too, to get the excess wax & polish out of all those little nooks & crannies.