Make your audience a part of your presentation. This is a dialogue, even though they aren't talking. They are laughing, listening, thinking, maybe shedding a tear. Give them room to have their reaction. Don't step on your laugh lines! I saw a captivating speaker this week who was surprisingly funny. Only problem was she stepped on every laugh line. When the audience laughs let them laugh. Give them room to react. Likewise when you tell a sad or poignant story. Don't rush from the sad parts right into your next thought. Allow them time to react. They are listening when you talk, but they are experiencing when you are not talking.