Great sugggestions. Studying for and completing a Personal Trainer certification is essential. The are a lot of certifying agencies–ACSM, ACE, NSCA, NASM, CSCS. Research them and decide which one best fits your needs. Keep in mind that certification is simply the beginning of your career as a Personal Trainer. Keeping current with the research literature and attending conferences and conventions to stay current are an ongoing necessity.
Good luck, Daniel