Laura Vanderkam has a nice piece about learning to speak in public despite being an introvert. As she explains in the New York Times,

You’d think that book writing would be a solitary endeavor, a perfect career for an introvert like me. But, as it turns out, a big part of book writing is speaking. Blogging isn’t good enough. To sell books, you have to talk to people about your ideas.

So what has she learned? First, “being “natural” comes from being practiced:”

the more you get up in front of people, the better you are at it. In the last five years, I’ve given so many speeches that it no longer feels nerve-racking. It just feels like Tuesday.

Second, “most of us are asked about just a few topics” and

after enough practice, you can know those topics cold. You can write speeches about them, do drills on the delivery and hone your ideas into phrases that sound good. Then you can memorize those phrases.

Finally, getting the first two down leaves you free to “focus on the part that’s fun: feeding off the energy that is always in an audience, and that can be harnessed if you try.”

Having just written several pieces about public speaking, I highly recommend her piece.