It has been observed that the more relaxed, laid-back, and cheerful the atmosphere during the lessons, the more people will make attempts and the more effective those attempts will be. This is of course determined not by the group itself but by both the manner in which the instructor conducts the lessons and his overall personality. It should be kept in mind that everybody already has enough serious things to deal with in life. There’s no need to add one more, and so the more jokes, funny stories from one’s own practice, self-deprecating humor, and anecdotes, the better. There’s no harm in humor. Actually, the more cheerful the instruction, the less people will skip classes and the more they will recommend you to others.