When I was younger, I had a terrible fear of public speaking. I would agonize before and sometimes after. There would be a shakiness in my voice and my knees, along with a dry mouth. I have come a long way since then and have given many successful public speeches in a variety of formats. A big key for me for public speaking is preparation, expertise, and passion. When I speak and have these three ingredients, the above troubles seem to go away.
PREPARATION: As an introvert, I do like to think about things. However, when you are behind the podium giving a speech or presentation, this is not the time to think. To prepare, think about the following questions: Who is your audience? What are the key points that you want to drive home? How much time to you have? Practice and get some feedback. When you are comfortable with the material, it will be easier to get your points across without having to think too much.
EXPERTISE: What is your expertise? How can you share it? Hopefully you are using those introvert thinking and studying skills to become or are in the process of becoming an expert in something you are very passionate about.
PASSION: Still nervous? What are you telling yourself? Maybe it is time to tell yourself a new story. For example, remind yourself you have something great to share and that people need to hear your message. If you are a perfectionist like me, you may need to tell yourself that you are going to give a great presentation, but you are human so it may not be perfect. Remember, all in the audience members are human and not perfect either.
When it is over, review how you did. Your next one will be even better.