You can use the Mr. Clean Magic Eraser or one of the generic versions of this product to clean varous parts.
USE EXTREME CARE!
It is an abrasive product and can remove graphics so
be very very careful if using it on a surface with graphics, like a playfield.
I cut the spongy material into small cubes 1-1.5 inches square. Instead of water, I soak the spongy material in rubbing alcohol and wring it as close to dry as possible before using it,