Public speaking is often seen as the ultimate in self-confidence. After all, if you can get up in front of an audience and talk from a platform, surely you must have amazing confidence. Well, yes and no. The truth is that public speaking is a skill that anyone can learn. You don't have to have amazing confidence to do it. But like learning any new skill, particularly one that involves overcoming a fear, this will boost your general level of self-confidence; which is why learning public speaking is so appealing.
The key to effective public speaking is to tell stories in which you have some emotional investment. Your emotions are what connect you with your audience. If you can get up on stage an relive an exciting or emotionally engaging story, and tie it to some lesson or point that you learned, people will want to hear what you have to say. The secret is to avoid going into presenter mode where you lecture people, which audiences hate. And the way to avoid lecturing is to tell stories.
Storytelling is fun, entertaining, and helps you overcome your self-consciousness in front of other people. Plus you'll find that if you tell personal stories, other people will relate to what you have to say and you'll get positive reinforcement from them, further adding to your growing confidence. To learn how to tell stories effectively, learn the 6-C model from Craig Valentine's Edge Of Their Seats Storytelling program.
Being vulnerable is sure to trigger some anxiety in you, but overcoming this so that you can be yourself on stage is the goal. Like any other skill, the more you learn about it and the more proficient you are, the more comfortable you'll feel. The best way to learn this skill is definitely by doing it. A little input from the professionals wouldn't go astray either, which is why I recommend you study World Champion speakers Darren LaCroix & Craig Valentine's Own The Stage program. Then get down to your local Toastmasters club and start practising!