In general: This will depend on your country and state, the types of people you help and who is paying you. Please check the specific guidelines and requirements for you and your area.
In America: There are currently no regulations on Laughter Wellness teachers, or any other types of Laughter Professionals for that matter. You do not need to be certified, registered, or licensed in order to offer laughter programs. This means that unless required by an establishment (e.g., gym or health club) instructors are not required to hold any certification in order to work as an instructor. In fact, some of the most experienced and well-known teachers have never been certified, registered, or licensed. That is because “Laughter Therapy” is a relatively recent concept, especially in regards to teaching it.