This is a tricky question. To be honest, it all depends on your comfort zone. Some people I have met can't go without their favorite pillow and will even go to extra length to bring that along. Some people I have seen can manage with just a tarp over their head.

If I may suggest:

A minimum kit (you MUST have with you at all times, even on a short day hike)
A lighter (waterproofed) with some strips of inner tyre rubber (tube) to help start a fire
A Fox40 whistle (used to attract attention)
A tarp or flysheet ( for shelter)
A knife (preferably NOT a foldable knife)
Some food bars (chocolate is fine)
Some strings or rope
Medications (if you require ay)
Basic first aid
Headtorch (make sure batteries are good)
A small billy (for boiling water)
A compass (you must know how to use one)

For an over nite
Choose either a tent (with a flysheet) or a hammock
Your MINIMUM kit above
A change of clothes for night sleep
Your hygiene kit (soap, toothbrush etc)
Extra batteries for your head torch
Your cooking kit and food
Extra garbage bags to keep clothes dry and also to take out rubbish
The above list I would say is your minimum. Other things you can add in.

Most importantly is that you need to know what you are doing. Having a first aid kit and not knowing how to use it is close to suicide.
Go with friends who have experience and never underestimate what the jungle is capable of.
Notify someone of your plans (where, when, who) for the trip so that they know where to look for you in case of emergencies.

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