The greatest nemesis of public speaking is the fear of it. The fear comes from a negative prediction of something that might happen. You might get a negative comment. No one will laugh at your humor. People will not follow your flow of ideas. You might forget a part of your speech in the middle.
All these fears are important. But you have to put out these fears on paper, so that you can deal with them in the best way you can. This way you can predict a great speech. Because the way you predict how you are going to perform is going to greatly affect how you will actually perform.
What were your negative experiences in the past?
What can you do to make sure that those negative experiences don’t happen again?