Cleaning the Nintendo DS housing without damaging it?

I found my old Nintendo DS again and that, what I now call "housing" is in pretty bad condition, was apparently painted with pencils, things scratched etc.

My question now: what can I do with it without being afraid to damage the material or even damage the Nintendo? I'm not sure if things like rubbing alcohol could be too aggressive

I guess as long as you don't shower it with it or larger amounts of it come into openings you can clean it with water as well as cleaning alcohol. Just be careful and don't let it run into the openings.