If you know how to sail, let everyone know! Even if you’ve only been on a sailboat once or twice, mention it. Sailing is not the easiest thing in the world and a lot of times captains (especially those sailing alone) will invite you on board just for the extra help with keeping watch or pulling in the sails.
Never been sailing before? Don’t worry; I’m sure you have some skill worth mentioning. The ones at the top of the list: cooking (you would be shocked by how many sailors can’t cook to save their lives), language skills (Spanish in the Caribbean is always welcomed), mechanic (even if you have never worked on a boat, they will teach you), and any entertainment skills (sailing can be incredible boring when you are out in the middle of the ocean – guitar players seem to be the most popular).