A clear objective

Most people start with a load of content and try to shoe-horn it into a PowerPoint show - instead start with the question: “What effect am I trying to achieve with their opinions and with their emotions?
2. Involvement. Plan to get your audience involved in the first 30 seconds - or less. They have to understand what is in it for them - why they should pay attention to you rather than their Blackberry or their own head noise?