I discovered these techniques by reading (although I don’t have the citations handy), used them myself and now recommended them to others. They include:
— Make your audience less intimidating in your own mind (one approach to doing this is to imagine the audience members to all be in their underwear — or naked, whichever makes them feel less intimidating to you)
— Stop concentrating on yourself (which fosters performance anxiety). Instead focus on your audience, and think about why THEY want the information that you have to share. If you focus on thinking of them, and how you can help them, instead of focusing on whether you can be a good speaker, it is more likely your message will come across well to them.
— If you find the size of your audience upsetting, focus only on a few people in the audience, and speak directly to them. If you have a whole auditorium full of people in front of you, choose one person (preferably with a sympathetic and interested look) in the front row, and one on each side of the room. If you alternate talking to these individuals, you will come across as speaking more personally to the entire audience.