You have to be really careful about what you do this with! Because you need an exterior light source for screen illumination, It'll pick out any little imperfections on your screen. The best thing to use is a record (LP) cleaning cloth, because they tend to be very soft and lint free. However, here's a good tip get few free AOL or some other free CD's to practice on and try out a few cloths! Use an Isopropol alcohol based cleaner, ie something that will lift dirt/ dust etc with out the need for heavy rubbing, and one that evaporates quickly with no residue. Get some finger prints on the CD and see what damage your new cloth does to the surface. Dont forget the CD is only slightly softer than your NGPC's screen so if you mark one, you'll mark the other. Experiment with combinations until you find one that is suitable. NEVER RUB THE SCREEN, WIPE IT GENTLY, keep the cloth in a sealed "jiffy" bag when not in use (The cloth will attract dust and grit which will scratch your screen!) Hope that helps?