How do I get over my fear of rejection? and insecurity?

It depends on your religious beliefs or if your a prude and disgusted by hundreds of naked people staring at you, Personally I would be, laugh. It can help to picture yourself confidently walking out in front of the crowd and giving your speach. keep that in mind they do want to hear what you have to say. Getting your thoughts in order rather than thinking about your clothes, hair. social status is a lot harder to do when facing a crowd but you can do it easily if you focus on your speach, the reason for giving that paticular speach. The little problems that crop up you must figure ways of dealing with in a very calm manner. really important for a good speaker to be able to do. Never get flustered or rather never show your flustered. George Bush was really really good at that inspite of how much fun was made of him because of his missused phrasing. Sarah Palin has good body launguage, bad speaches in my opinion but she comes across well because she looks confident when she is talking up on the podium. Pretend your like those people to practice. Only be better.