Be prepared for rain. It goes without saying--this is a rain forest, after all. Instead of a rain jacket, bring a poncho with a drawstring hood. The poncho will better protect you and your backpack during downpours and packs smaller than a rain jacket. Leave the umbrella at home.
Bring trashbags and gallon-size resealable plastic zipper bags to protect your backpack, camera and other gear from rain.
Prepare for mosquitos. Mosquito repellent and anti-itch lotion is a must. Many travelers bring repellent containing the insect-deterring chemical DEET, but others prefer more environmentally friendly products such as those made of chrysanthemum oil. Also bring a foldable hand fan, because the breeze it will create can help keep mosquitos off your face. And long athletic socks that you can pull over your pant cuffs will provide an extra layer of protection against mosquito bites on your ankles. Also bring bath products (soap, shampoo, hair care products) without fragrances that could attract insects.
Pack long-sleeved shirts, long pants and other clothing made of quick-dry, breathable wickaway fabrics. Most travel outfitters sell them.
Don't estimate the power of the sun. Even under the cover of a canopy of rain forest trees, you still can get sunburned. Bring a hat, sunglasses, lip balm and sunblock.
