To become a scuba instructor, you need to have been certified as an entry-level diver with any agency for at least six months before you can start your instructor course. You also need Advanced Open Water, Rescue Diver, and Dive Master certifications. You need to be a certified Emergency First Response instructor, have logged 100 open water dives, and successfully completed the instructor development course, which is usually a 10-day course. During the course, you learn how to work with students, handle problems, present dive theory, and demonstrate concepts effectively.

You can then sit the instructor evaluation exam, a 2-day affair which includes presentations, mock instructor scenarios, multiple written exams and more. The instructor evaluator comes from the headquarters to judge the candidates and certify instructors.

Do your research! Find a course director that you like in a part of the world that you want to go visit. Find out when the next instructor development course is and sign up.