Luggage and bags:
one piece and carry on(unless you can fit in one carry on)
Clothing/Shoes/Weather Gear: little as possible, you can wash your clothes every day if possible. Bathing suit and shorts with a few tops. Nothing formal. Comfortable flip flops and a pair of tennis shoes for walking. No umberellas-too much trouble for the price. No jewerly-who do you know that you have to compete with!!!
Toiletries and Medical Supplies: soap, shampoo ,wash cloth, suncreen, small first aid kit, DEET for bugs and your main medical medicine that you take every day. Also TUMS!!! I also get a prescription for the "VIRUS" just in case, that I take everyday. Otherwise bring Imodim AD.
Photo Equipment: Your own camera that will go in the purse or pocket. Don't leave it anywhere!!!!!
FLIP FLOPS are a must! Light-weight clothes, it gets really, really hot.
Toiletries and Medical Supplies: Bring or purchase suntan lotion...I've never been so badly burnt in my life. I'm serious. Also, skin-so soft, mosquito repellant..everything that will prevent bites....I got about 37 bites. no joke.
Photo Equipment: It's hard to bring a bulky camera bc there are so many 'active' things to do..so maybe something small, like a small digital or a compact camera.
Luggage and bags:
Pack what ever you can carry.
Clothing/Shoes/Weather Gear: A rain jacket is a must along with shoes you don't mind getting wet.
Toiletries and Medical Supplies: Normal common sense.
Take plenty of sun screen. It dosen't take but just a couple of minutes to become a burnt piece of toast!
Photo Equipment: Batteries and film cost a little more so bring plenty of each with you.
Camping/Beach/Outdoor Gear: There are tons of places for back packers to hang a hammock or pitch a tent that are well within budget.
Miscellaneous: As with any tropical location, there are insects that bite, eat, chew or sting no matter what time of day it is. One couple in my group used Deep Woods Off but they got bitten a couple of times. I used 100% Deet and didn't have any problems.
Deet can be found at any outdoor stores.