A boat trip means plenty of exposure to the sunlight. While everybody loves the sun, nobody really loves being sun-burnt. A sunscreen is absolutely essential, but make sure the SPF is high enough to offer the required protection. You can take it a step further by going for clothes that offer protection against the sun. This includes sarongs, cover ups, hats and sunglasses. It will not hurt to bring along an Aloe Vera based cream too. This will help in the unfortunate event that you get sun-burnt. Don't forget to add shampoo to your bag too as the constant exposure to salt water can ruin your hair.