The first place to start with selecting kettlebell instructors are their levels of certification. Are they certified? That helps, but a few letter stamps at the end of their name isn't enough. Some certifications are only a few hours, while some are several extensive daylong programs.
A kettlebell instructor needs to know how to teach and how to coach you along the way to reach your goals. You also have to “click” with your instructor and be confident that you’ll enjoy and have fun in classes. The best certification is your certification: try some classes and make sure that an instructor will be a good fit for you.