Hi Eugene: Each teacher has their own version of themselves and allowing that natural and sincere person out of the bottle will reveal the confident, competent instructor ideling inside. Delivery and presentation are the only visible evidence of waht the teacher is thinking, conveying, their point, or their knowledge. Being relaxed and calm helps create that for the class. Humor can season a lesson if not overdone. I think of the metaphor of the teacher as a tool. Our focus is not the tool, but what it can accomplish. And their thousands of specialized "tools" that can potentially be very effective in accomplishing their goal. Regards, Barry