I have found in the many talks I have done the best way to burn time with content is to get them involved. Show them items to pass around invite questions, bring examples of what not to do, what to do, a small piece of wood for each that they can shave to one ring with a knife while they are listening, Etc. get them doing something, Have an outline to keep it on topic and it will move of its own free will, they will enjoy it and so will you.