One of the basic criterions to get through with the Scuba Certification is to be physically sound. If you are not physically fit, then always get in touch with a doctor before certification. Several agencies are guiding and providing the study materials to be certified. It is most important to choose the instructor that you trust and feel comfortable with. It is suggested to stick with an instructor whom you are comfortable with. In addition before opting for some instructor don’t forget to check their reputation in the field.