1. Know your material. Pick a topic you are interested in. Know more about it than you include in your speech. Use humor, personal stories and conversational language – that way you won’t easily forget what to say.
2. Practice. Practice. Practice! Rehearse out loud with all equipment you plan on using. Revise as necessary. Work to control filler words; Practice, pause and breathe. Practice with a timer and allow time for the unexpected.
3. Know the audience. Greet some of the audience members as they arrive. It’s easier to speak to a group of friends than to strangers.
4. Know the room. Arrive early, walk around the speaking area and practice using the microphone and any visual aids.
5. Relax. Begin by addressing the audience. It buys you time and calms your nerves. Pause, smile and count to three before saying anything. ("One one-thousand, two one-thousand, three one-thousand. Pause. Begin.) Transform nervous energy into enthusiasm.
6. Visualize yourself giving your speech. Imagine yourself speaking, your voice loud, clear and confident. Visualize the audience clapping – it will boost your confidence.
7. Realize that people want you to succeed. Audiences want you to be interesting, stimulating, informative and entertaining. They’re rooting for you.
8. Don’t apologize for any nervousness or problem – the audience probably never noticed it.
9. Concentrate on the message – not the medium. Focus your attention away from your own anxieties and concentrate on your message and your audience.
10. Gain experience. Mainly, your speech should represent you — as an authority and as a person. Experience builds confidence, which is the key to effective speaking. A Toastmasters club can provide the experience you need in a safe and friendly environment.
Taken from: http://www.toastmasters.org/tips.asp