*Quick drying is important, because if you’re in the rain forest, your clothes WILL get wet. You can buy clothes that advertise themselves as quick drying but it’s not necessary. Just use some common sense. Remember nylon dries faster than cotton, so does wool. Basically anything synthetic or wool is going to be faster drying than cotton. Thinner, lighter fabrics also dry faster but be careful, too thin can also rip easier and the jungle is hard on clothing. Thick nylon is better than super thin cotton.
*Clothes should be tough. Strong fabrics are good not only because they won’t be ripped by thorns, branches, rocks, etc. but also they protect you from those things as well. The jungle is full of things that can scratch, cut, sting or irritate your skin. It’s nice to have a tough piece of clothing with long sleeves protecting you, at least at first.
*The longer you’re in the jungle and the more you get used to the environment, the more you might want to “go native” wearing less clothing. By all means, try it out, this is where a small pair of nylon shorts and a sports bra (if you’re female) or nothing (if you’re me) come in handy. Just make sure you also bring more protective clothing as well, this can be harder to pull of than you think.