As I've mentioned in other threads, for years I've been using Nu Finish on my lacquered instruments. It's not a wax, and it isn't a polish in the sense that a lot of typical polishes are. It's more properly described as a "protectant", and it has the feature of filling in any micro-scratches in the surface of lacquer while not "wearing off" as readily as waxes.
Nothing wrong with products like Pledge (which are cleaners but not surface protectants) or a wide variety of waxes available, but in my experience Nu Finish does a better job. It does take a bit more effort to apply, and so if you're just concerned to wipe a smudge off the surface, then something like Pledge or even some rubbing alcohol or just a damp cloth will be quicker and easier.
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)