I realize i lack of this in speaking in public.
I am going to try to build up on this, a big idea i got from "How to develop self-confidence & Influnce people by public speaking, i think the first main thing is that we need to be ourself when we speak.
Be who you really are, and not fake it when you are up on stage. If you are nervous, then just mentioned it, i think people dont mind at all.
Then next i will do is you need to be practicing. The main thing is be as ready as you can by practicing. Keep doing it no matter what and imagine yourself speaking.
Next is knowing the topic. If you are familiar with it, its much more easier to deliver the speech or the content of it. It takes even more exposure to be very spontaneous on stage.
Other than that, would be always keep yourself well rested, and be as high energy as you can when you speak to a crowd. It doesnt make sense to speak in a tired or sleepy voice.
Hope this can help and remind myself on this note above. Happy trying and be confidence in speaking!