Just rub it on a clean piece of white paper and/or on your finger. You'll see when it's clean and get the hang of it quickly.
If you get a chance to clean the surface grime off of any back covers let us know - it's a magical moment when you see how easy it is (don't do very old Golden Age or early Silver Age comics which have less gloss on the back covers; only do it to Bronze Age and late Silver Age books as they they tend to, moreso, have glossy back covers).
If you get a chance to clean the surface grime off of any back covers let us know - it's a magical moment when you see how easy it is (don't do very old Golden Age or early Silver Age comics which have less gloss on the back covers; only do it to Bronze Age and late Silver Age books as they they tend to, moreso, have glossy back covers).
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