I use the E-Z Wipe product that comes packaged free with Duracoat and Apex foils. It is like a wet-nap you get in a restaurant except the solvent is 99.7% Anhydrous Isopropyl Alcohol (also called isopropynol). It works fine. You can also use the solvent itself, available at most chemical distributors, applied to a lint free cloth or paper. The main thing is to make sure it is the real deal, 99%+ anhydrous, meaning water-free.