Nervousness about preparing for public speaking

Sometimes presentations make me a basket case.

This week's Friday presentation is no different.
Except, with just having my group in the room, we're adding a group of first years, armed with questions and another teacher.

Based on the marks in the past, my presentations aren't bad. I need to work on my conclusions (its in the works) and minimizing my rambling. These areas are works in progress.
This week's assignment is a news conference. I've been a part of them in class, but not on this level. Not when I am expected to play the role of a surgeon.
In the last two nights, I have had a nightmare each night about this conference. I have no idea why, its not like I think I am going to fail. I'm more worried about getting asked questions that I won't be able to answer. I've research everything I could possibly about medicine, what it takes to be a surgeon, and our incident. That should be enough.

Deep breathing is everyone's friend.

The thing about public speaking and myself is that once I begin, I am fine. I take a deep breath and then begin. This is my best coping strategy. Actually, my best strategy is just to think about what it will feel like to be done the presentation.

Any suggestions for coping strategies, things you do during the presentation to keep you on topic, or things to look at to keep the flow moving?