I have a game with a dirty box, do you have any tips on cleaning it?

Something we try to do if we scan a box which is a bit dirty, is get a very slightly damp cloth and just softly wipe the box and then dry it immediately with some tissue or absorbent cloth. However, you need to be very careful because this can damage it.

It may be better to just scan it and hope that it can be cleaned up using an image processor. In this case it would help drastically if the dirt is on a low detail area.