If you want to succeed in lean, you need to develop your capabilities and help others do the same. You need to change the way you think and act as a leader and a team member. You need to learn how to coach others and yourself, how to solve problems and improve every day, how to follow the best practices and make them visible, and how to appreciate and reward the hard work and excellence of your colleagues. 

Check your progress and get certified by using some frameworks and standards, which tells you if you are a practitioner, a leader, or an expert in lean. But remember, developing your capabilities in lean is not something you do once and forget about it. It is something you do everyday, and learn from it every day.