Contrary to what you may think, a boat toilet is easy to use. There is a drainage system with a manual (or electric) pump (depending on the boat) that takes the water and drains it to the waste water tank. It is very important not to throw toilet paper and objects of any kind in the toilet to avoid obstructing it. Follow in any case the instructions during the process of check-in of the company and ask the skipper in case of doubts.