Seek an opportunity to speak. Ralph Waldo Emerson said, "Do the thing you fear to do and the death of that fear is certain."
Prepare your talk, outline it, write it out, make notes, and wallow in the material. Rehearse it aloud until you are sick of it. Then go through it one more time.
Focus on one pair of eyes at a time when delivering your speech. Your butterflies will fly away.
Use analogies to support the points you are making. People remember vivid mental images longer than they remember words.
Speak up. Speak out. Speak loudly.
Try to hold back or be reserved as a speaker. The maggots of nervousness feed on that, and they'll eat you alive.
Bring your hands together. Once you do, they'll establish a relationship and work in parallel. You need them operating one at a time to create excitement.
Think you can solve nervousness by reading your talk. It takes a lot of training and experience to do that well. And the audience doesn't like it when you do.