A lot depends on the particular jungle. Locations with nearby areas that drain and dry out make a fire much easier and much more practical.

Lowlands, and other places that never dry and pretty much everywhere in the rainy season, can makeing a fire a major problem as absolutely everything can be saturated. Getting a fire going is just the beginning as finding sufficient material to keep it going can be a trick. A handy method is to keep a considerable amount of wood close to the fire to dry so you are manufacturing your own firewood. Laying a couple of small saplings across the fire gives you a place to work off and both dries and cuts the wood for you.

Of course, if you are traveling through, or working hard at getting out or rescues, as opposed to taking up housekeeping, spending that sort of time and energy to maintain a fire for a night is impractical. A more practical approach is to bring a stove or some sort and use fuel you carry in. A small stove is practical because it pays you for the weight with faster setup, quick cooking, and energy savings not having to work hard as assembling/ maintaining a fire. Staying well above freezing butane stoves are light, cheap, and effective.

Also, as most people know, jungles are buggy. The variety and numbers is what shocks people. Do not underestimate how buggy it can get. Have a spare head net on hand. Lightweight and cheap there is no reason not to. A reserve supply of bug juice, the tiny travel bottles are handy, is wise.

A hammock is a big help keeping critters off you, getting you above the wet ground, and keeping air moving so your skin won't rot. A horizontal line rigged over the hammock to hold a tarp and mosquito net makes a nice shelter that keep you dry from water from above and below and the crawling and flying beasties.

Bring your walking stick with you. Some jungles are notorious for having no solid wood that isn't three feet in diameter or one hundred feet above ground. A walking stick is handy for swampy and uneven ground, and crossing the creeks that form in a few hours when it rains.

Jungles are also sometimes dry. Everything may be saturated but after the rain stops and water runs off or soaks in finding water to drink can be a trick. Some vines and plant stems can store considerable amounts of water. Learn about the plants that hold water in your area. Given the possible difficulties boiling water plan of using a filter or chemical treatment.