Clothing/Shoes/Weather Gear: Dont forget to bring your gym shoes. The resorts have a lot of rock climbing and other activities, but they wont let you participate with out gym shoes. I am planning our second trip now and gym shoes were the only thing we didn't bring and actually needed. I will defenitly be bringing them this year!
If you plane on going to Dunns River Falls, bring water shoes! They do have them available for purchase at the park, though, if you forget.
Toiletries and Medical Supplies: Bring plenty of sunblock especially if you haven't been out in the sun much before your trip! I noticed the tendency to sunburn easier here. During the time we were there, I really didn't notice much mosquito activity or even flies. Once, we saw some wasps/bees but that was higher up in the mountains near Browns Town.
Also, I would bring your basic Tylenol, Ibuprofen, Aspirin, etc, you can probably find it in the local market, but it was a few blocks walk.
Luggage and bags:
Bring a day pack to take with you on boat trips, preferably something you don't care if it gets wet
Clothing/Shoes/Weather Gear: Shorts, short sleeved tops, bathing suit, sandals, tshirts, sunglasses. I usually pick a couple of shirts per day in case of sweat or them getting wet. Tshirts take a long time to dry in the tropical climate.
If you are staying at an all inclusive resort, ladies should pack a dress/sundress, men should pack long pants, collared shirt and closed toe shoes and for the really nice places some require a jacket as well (although they usually have loaners)
Toiletries and Medical Supplies: Bring lots of sunscreen, the sun in Jamaica is intense
Photo Equipment: If you use a digital camera, you may also want to bring a disposable waterproof camera for snorkeling and Dunn's River Falls or a disposable camera to take along on boat trips. I'm always uncomfortable taking my digital along on water related activities.
Camping/Beach/Outdoor Gear: Although the resort and boat operators usually have snorkeling equipment, if you have your own mask and snorkel, you might bring them along in case you find a nice spot from the shore
Miscellaneous: Bring a good book, I always bring a fun novel on vacation (Harry Potter on this one) and all the magazines I haven't gotten to
Luggage and bags:
Pack light! You won't need much. Bring a bathing suit, a cover-up and one nice dress (or pants and a collared shirt for the men) for your evenings out. Most of the time you can get away wearing just a bathing suit or a pair of casual shorts and a t-shirt.
Clothing/Shoes/Weather Gear: If you're doing the Falls tour bring a pair of water socks (you can buy them there for about $13us) or a pair of old sneakers - I used a pair of old Keds and was fine. These will also come in handy if you go mountain biking or horseback riding.
No need to bring your scuba gear. It's included at the resort. And wetsuits aren't necessary. Trust me. I get cold very easily and was just fine.
Toiletries and Medical Supplies: I had been warned by a friend to bring a supply of pepto, immodium, etc., anything you think you might possibly need. The reason being, you're on an island so things like aspirin, etc will be much more expensive over there. Even if you never use it it's nice to have it with you. Just buy the travel size.
Sandals provides each couple with a welcome pack that includes healthy portions of shampoo, bath gel, aloe vera gel and lotion.
Don't forget the sunscreen!
Photo Equipment: Bring a waterproof camera - the disposable kind will do just fine. And bring lots of film... It's gorgeous over there.
Camping/Beach/Outdoor Gear: All the beach gear you need is provided by the resort. So don't worry about bringing anything yourself.