I just thought of droping these lines to add something to the helpful mentiened ideas.every public speaker has to bear in mind that
as a humain being,no one on the face of the earth can proclaim that he doesn’t feel afraid of standing in front of a crowd.my point here is that feeling a fraid in such setuation is something purely natural,so we cannot triumph over it,the only alternative that is left for us is to learn how to speak in public while we are afraid.