Hi Tiley,
A couple of things I learned whilst in the Jungle;
Stay hydrated, ensure you have either Iodine or Chlorine purification and two water bottles, so that one can be being purifying whilst the other is ready to drink. Where we were water was never far away but be safe before drinking it.
Never put your hands where you can't see. Although we didn't come across any real nasties they are there and again better safe that sorry.
Step to to and off logs, don't step over them as snakes enjoy kipping under logs and if you startle one it may take offence.
If you are going to be wading in water for most of the day, jungle boots are a must as they have drainage points and help prevent immersion foot.
On that subject take the time at the end of the day to dry and treeat your feet, a good athelete foot powder is great as it absorbs remaining moisture and kills fungal spores.
Take it slow and enjoy the world around you.
Avoid sitting directly on the leaf litter as it's home to scorpions etc, a bit of kup mat or a nice big leaf makes a good bum protector.
If your using a machete or parang be very careful, they occationally take on a life of their own - ensure you have a big decent dressing just in case.
Mossies can be a pain and the day time mossies can carry Degue Fever so along with a wide brimmed hat (or baseball cap) - which will help shed those dangling ratan vines that have little sharp hooks on them - take a head net. I beleive only had to use mine once but glad I had it.
A decent anti mossie spray is essential - DEET works best but take your sunglasses off before you spray your face.
If staying overnight, camp well above the rivers as they can rise by 2m very quickly.
Treat any cuts and scratches immediately as infection can start very quickly - iodine spray is good here and waterproof plasters - although they won't last long
The jungle is a wonderous place full of sites and sounds completely outside our temperate experiences and it's easy to hype it up as a dangerous place but it can be. If you take your time - especially if your not fully acclimatised - are aware of what you are doing it's a real pleasure.
Good luck with the trip and don't forget the camera ( a waterproof one if you can ) and post the pictures up on your return.
Best wishes
David