Remember that the audience wants you to succeed. Watching an uncomfortable speaker makes an audience uncomfortable as well, so they will be on your side when yo

Remember that the audience wants you to succeed. Watching an uncomfortable speaker makes an audience uncomfortable as well, so they will be on your side when you take the stage. Rehearse like crazy and visualize yourself speaking to the large crowd. It's possible the stage lighting will be so bright that you won't be able to see the audience when you present. If that is the case, visualize your most successful practice and pretend you are speaking to that smaller group again.