Our ocean breezes are delightful at keeping bothersome things (mosquitos) to a minimum. On calm days, beach sand flies can be irritating. The usual bug repellents are helpful. Hydrocortisone cream helps with itching. When making an excursion in to the rain forest, it is wise to have long pants and long sleeve shirts, as well as hiking/running shoes or boots.
Remember you are coming to a subtropical climate and the sun can be intense. Be sure to bring plenty of sunscreen and a hat.
Our sandy beaches and shallow areas around the pier are delightful to enjoy. If you are not used to walking a lot on sand and have "tender feet" having beach sandals and/or water slip-ons is a good idea.