Drinking Water
All in all, sustaining yourself in the jungle is very important. Fortunately, there are a lot of sources of drinking water everywhere, so you will have at least that one in abundance. Never ever drink dirty water or you will get sick. If you can't find drinking water around, then take a coconut and cut it in half. Leave the two halves on the ground near your shelter, and when it's going to rain the halves will collect the rainwater, which is good for drinking. This way, you will always have drinking water around.
How Do I Manage Sanity?
You should keep your sanity up by at least 80% to make sure that you wont even start hearing voices. At lower than 50% sanity, those tribal hallucination will start spawning and acutally deals damage to you.
Things to do:
Eating well roasted meat.
Staying near fire.
Sleeping in a good quality bed.
Taking off leeches.
Things you should not do:
Eating insects.
Leaving diseases untreated, especially worms and leech.
Sleeping without shelter.