Beware of the tales of your Caracas taxi-driver or of your Cayenne restaurant waiter : They will undoubtedly tell you about a friend having been attacked by a jaguar or a cousin maimed by piranhas. You will surely receive so many warnings that you will feel like booking immediately at the nearest Club Med.
This in no way corresponds to the reality of the rainforest.
All this mythology or even mythomania only emphasizes negative aspects, potential dangers and frightful diseases. It only refers to disagreeable or violent experiences whereas, as long as it is approached with respect, the rainforest is strong, but its strength is subtle and finely shaded.

To achieve this aim, you must first choose the TYPE OF HIKING TRIP that corresponds to your personal taste and your physical ability.
There are many ways of discovering the forest. From a 300$ a night Lodge to so-called "survival training" experiences.
Everything depends on your wallet, your age, your physical condition and especially your centers of interest.

The quality of organization : always choose an agency specialized in this type of trip.
The quality of the guides : their experience and technical competence are of foremost importance.
Avoid large groups. Ask your agency for information about this. As far as I am concerned, in order to be interesting, a walk through the forest should include no more than ten people.

Having thus decided, you can choose to use a camp as a base to tour around the area or leave for a hike that lasts a predetermined length of time.
Many of such trips include going up or down rivers which are often the only means of penetration. If these boat trips allow you to discover a remarkable fauna (taking into account that the larger and busier the river, the lesser the chances of seeing animals), they can, in the long run, become tedious and tiring, especially under the burning sun of the dry season.
In any case, you will have to make sure that such trips include hiking through the forest and not be a succession of bivouacs along the riverside as it is sometimes the case.
Otherwise you will only see the edges of the forest.

Otherwise you will only see the edges of the forest.
Don't let yourself be fooled by the present media craze for "the extreme". In order to appreciate the rainforest, you need time, patience and unpretentiousness. Forget the "camel trophy" or "raid gauloise" spirit, you will not discover the forest like this. These "adventures" (a very hackneyed term nowadays ! can those loud and mediatized commercial undertakings be really called adventures ?) consider the forest only as a pretext, an obstacle to be cleared.
If you have the urge to spin your wheels through mud or run with a rucksack, you don't need to travel so far !
No need either to lift 120 kg weightlifter style… forget Rambo. Life in the rainforest cannot be based on confrontation. It is a matter of adaptation. This does not mean to say that your experience will not eventually be athletic, on the contrary, but if physical performance is your only motivation, you will only see the negative aspects of the forest, which is a pity.

In short, prefer the Humbolt to the Pizarro approach !

The dry season is generally recommended, but this notion is subject to caution under the Equator.
If you plan a trip that includes many bivouacs or an expedition, choose preferably the dry season. You will see more fauna on and close to the rivers. Fishing is easy and abundant. There are few or no mosquitoes in the primary rainforest. On the other hand, be ready to suffer from the heat during hikes, and protect yourself adequately against the sun during river journeys.
Another inconvenience is that walking on dried leaves in the forest can be very noisy.

Thus, if you are a distinguished entomologist, leave during the rainy season, there are many more insects then.
If you like photography, the flora is then more exuberant and colours are more distinct. Forest soil is very humid, saturated with water. You can walk silently, thus increasing the chance of observing the fauna.

If you are a "generalist", try to avoid the extremes : the big rainy season, lasting generally two or three months a year during which you might have to spend long hours in camp, watching the rain fall. Camping can be difficult. Fish are scarce, the level of the rivers is so high that water invades the banks, and fish have more than enough insects and other small creatures to feed upon. Even piranhas are rare !

The "bid dry season" is the scorched earth period during which farmers set fire to forest zones that have been cleared in order to sow before the first rains. In certain regions, these fires are so large that vehicles have to run on low beams during the daytime and airports are closed. The air stings throats and eyes….

This is relatively unimportant if you are going to spend four days in a Lodge in Costa Rica during the tourist season.
But if you have to spend several days camping in faraway regions with limited comfort, lack of privacy can have devastating effects.
Some people are simply incapable of living under such conditions.
They usually do not know it when they leave !
You will see that it will usually be the same one who "forgets" his turn at wood-gathering or dishwashing, the same who goes swimming when camp is being set up, or who will complain about the food that he hasn't even prepared himself.
Some people react badly to hardship (repeated efforts, danger) and become irritable or disagreeable.

Chronic hypochondriacs are also hard to bear.
You will have to endure during breakfast a detailed description of their nightly intestinal disorders. This usually are the male types….
My personal experience has shown me that women are generally better companions in difficult circumstances : they are calmer, often more resistant and less prone to "flip out" !
Do as you would if you were going on a boat trip. Eliminate elements that would create tensions within the group.

Here again the comparison with the navy is pertinent. A bad skipper will render your cruise uninteresting and even dangerous.
A good forest guide must be experienced and have a profound technical knowledge of the fauna and flora.
You will be assured of the quality of the set-up and the guide if you go through an agency specialized in ecotourism.
For those who love birds, many agencies (especially in Anglo-Saxon countries) offer trips specialized in birdwatching with highly competent guides.

Lightweight cotton clothing. Synthetics are lighter but their feel is disagreeable when you sweat (which is often the case !).
No jeans, too heavy.
Hardwearing garments. The choice depends on your wallet, but you get very dirty in the forest : your latest "jungle by Armani" style outfit will soon be covered with mud, fish scales, etc.
A lightweight "K-Way" type raincoat.
Good walking shoes. No need to take heavy trekking shoes, but no canvas shoes either, humidity tears them. No rubber boots, true nest for mycosis. Lightweight "trainers" or sneaker type shoes will become stuck in the first mud puddle during the rainy season.
A lightweight cover or sleeping bag.
A lightweight sweater or sweatshirt for cool nights.
A forehead lamp with at least one spear bulb. No large flat batteries, they cannot be found in South America (apart from French Guyana).

For bivouacs, hammocks, mosquito nets or tents are usually provided by the agencies. If you organize your own trip, know that the best way to camp in the rainforest is to stretch your hammock between two trees and protect it with a plastic sheet well stretched on a cord.

According to me, the best equipment is a large cotton hammock. They are warm and agreeable to touch. Avoid wetting them, they become heavy and fragile. The mosquito net must be large compared to the hammock and made of not too delicate material so as not to tear. It should not touch your back, the eventual mosquito will bite through the hammock…

Avoid expensive jungle hammocks with attached mosquito net and roof, found in specialized shops. They are made of nylon or other synthetics and will make you sweat abundantly during hot nights. They are also hard to install with a whole system of cords, which will make you stumble when you get up.
Also avoid net-type hammocks, lightweight and not bulky but cold and very uncomfortable on naked skin.

Resist your will to buy a machete, even though it is an essential piece of equipment for life in the forest. It is a particularly dangerous instrument for the inexperienced. Sharpened with a file, it can have a fearsome cutting edge. It has to be used with a quick movement of the forearm, at a certain angle. Otherwise, the long and flexible machete can jump back like a spring.

Accidents are very frequent, any person used to the forest has had severe cuts with his own machete or has been victim of others' carelessness. Even a seasoned bushman gets tired if he has to open the way in front of him during several hours. The forearm begins to hurt, blisters appear, hands become sweaty.

I can assure you that I become particularly nervous when a novice starts to use his new machete behind me during his first walk through the forest…
A good Swiss knife is an excellent companion (you will probably use only 3 or 4 blades out of the 65 available). Take one of the latest models, simpler to use, with a longer blade.

As far as the magnificent, shiny and expensive Rambo knives made of stainless steel, their most useful element is the bottle opener at the top of the blade, unless you have to cut up and skin some big game (?).

Buy your compass in a specialized shop. The best ones are the plotting compass, avoid those included in other instruments, especially metallic ones.
As far as photo & video equipment is concerned, the very humid conditions tend to provoke power-failures due to oxidization of the contacts. Keep your equipment dry by using water-proof plastic boxes and dehumidifiers.

Finally, if you leave during the rainy season, a totally water-proof rucksack can be a good solution, but it is not very practical, being navy bag type, and it has to be emptied to find something at the bottom…
In this type of condition, garbage bags of all sizes are very useful!

I will not elaborate on the subject since tourist guidebooks treat it extensively. Here are just a few useful tips :
For preventive treatment, take the advice of local doctors, they know the country and are used to treat certain ailments.
In general, it is more likely that you might catch something in the urban zones of South America than in the depth of the equatorial forest.
Don't despair at the first appearance of a sore, a redness or a pimple. If something seems dubious, show it to your guide or to a native.
Be philosophical about small creepy crawlies that can cause disagreement. Their abundance is a consequence of the richness of the forest ecosystem.

Don't forget to take athlete's foot preventive cream. If you have to walk for a long time, especially during the rainy season, apply it to your feet every day as a precaution. It is important to keep your feet, and thus your shoes, as dry as possible. Don't walk in the water with your shoes on, take them off as often as necessary if you have to ford a river. Have a change of one or two pairs of socks at hand.