Welcome, hope you'll love it as much as we do.
You get a map on arrival, Water points to fill your water up are easily accessible in many locations, so are different toilets. Read the FAQ from A-Z on the Fusion website, most of your questions are answered there.
Food is absolutely affordable in my opinion, and mostly also healthy, always vegetarian or vegan (and not all this meat substitute stuff, but often GREEN).
I'm not worried about being robbed, the vibe is generally very good. But no need to be stupid unnecessarily either. Also, when the Fusion opens for the "main public" on Sunday, then the risk of theft (intentional or not) increases. Many leave on Sun/Mon as well, meaning there are not "eyes" everywhere to see possible thefts.
You shouldn't go out peeing in the bushes at all, really. Not cool. There are enough toilets (of various types) for everyone (also on the map) even if the lines are long -- they often move fast.
Check these threads out as well:
https://forum.kulturkosmos.de/viewtopic ... er#p185356
https://forum.kulturkosmos.de/viewtopic ... ks#p186960
And don't be TOO prepared. Half of the fun is the journey.

It's not about making the world a better place; it's about making ourselves better persons. The rest comes naturally.