Clean it with a strong cleaner first, then see how faded it is. If not bad then a good auto polish should work. Watch the decals, they can be peeled right off with certain cleaners and polishes. If really bad, peel off the decals, sand and repaint. New decals are availiable. I just use a simple spray on car polish/wax. Easy on, easy off and it keeps everything like new. Only takes a few minutes to do. Also use it on my aluminum hull, makes the crud from the water come off much easier.