The size of your audience has a direct effect on the types of humor which are most appropriate, the expected audience response and the timing of the presentation.Members of very small business groups tend to be too self-conscious to laugh much. Use short one-liners. Be brief and informal with your humor; don't use any long stories or jokes.In small groups laughter will come more quickly. It's now OK to stretch to jokes and short stories. Your presentation will take less time to deliver than to a large group.A presentation to very large crowds in enormous rooms or venues such as stadiums will take longer to deliver because laughter comes in waves. The portion of the audience right in front of you will laugh first. Then most of the rest of the crowd will laugh. The third wave will come when those slower to get the joke finally do, and when those who laugh because everyone else is laughing kick in. You must allow time for this phenomenon to occur. In large crowds you must play to the back of the room. These people are hardest to reach.Why do you need public speaking to boost your career?