I'm a lifelong stutterer and current anxiety basket case (recent on that).
I've spoken before 4000 people at a major trade show keynote and serve a spokesperson for my company with one-on-one press and other audience events.
Here are my tips:
1) Rehearse but DO NOT do it word for word. If you're anxious ask a group of friends or family to be the audience. [I do neither of these but some say it helps. I rehearse talking points only]. Strive to keep it conversational versus canned.
2) Tell yourself that you know more about what it is you're saying than the audience does. Think "I've got something to share". This is a confidence builder.
3) Get animated. I don't mean jump up and down but get involved when you're speaking. That way it feels more natural. Above all, do not stand behind a podium. Use your hands just like you do in normal conversation.
4) You're shaking like a leaf like I was in front of 4000 people. Seriously thought everyone could see my hands shaking while doing a product demo. Guess what, no one noticed it. Focus on the execution...absolutely everyone gets nervous but the audience is largely oblivious. Yes, your lips will be super-glued to your teeth at this point. They don't notice this unless you start to compensate. Just go with it.
5) Speak forcefully, friendly and approachable. Unless you're a CFO delivering earnings results you can do that. And to re-iterate, don't do it behind a podium.
Hope that helps. If you shake like a leaf no one will see it because the rest of your delivery will be dead on