There are some things you need to pack to make the trip more enjoyable. An underwater camera or a good book are good examples. Bring one of each. It is also a good idea to use gadgets that you can use for various purposes, for example, an underwater camera for both dry and underwater excursions or a universal charger for all your electronic gadgets.
Use Plastic Bags
Plastic bags are very useful for keeping toiletries in place as well as for storing your used clothes. You can put used swimsuits in these bags and avoid worrying about them mixing with your fresh change of clothes.
Wear One Outfit On You Way To Your Destination and Back
This is a great way to lessen the change of clothes you need to pack. Most people pack according to the number of days of the trip, forgetting that the last day will often be comprised of travelling home.
You can easily wear your first-day outfit on the last day, or even reuse a fairly clean one that you have worn previously. As long as you have a clean change of underwear, no one would notice and you get more room in your luggage for souvenirs and other stuff that you may want to take home.
Place Important Papers In An Accessible Place
Avoid having to rummage through the entire bag for your airline ticket or your money. Use a smaller shoulder or sling bag for your wallet and important documents to make them easier to reach.
Travelling is much more fun if you are not lugging heavy luggage around so pack light but make sure that you have everything you need.