Confidence
Avoid confidence, relying on yourself to overcome your fears. The problem in telling someone to be confident (whether they are about to make a speech in front of everyone they know or whether they are about to walk into a dark room when all signs tell them that eyes are watching from within) is that where does one suddenly get confidence when someone tells one to?
All you need is confidence, how simple, why haven't you thought of that before? Confidence is feeling certain of your abilities and finding your inner strength. But no one tells you where it is, where to look, or how to keep it once you suspect you may have a spark of it. Though this spark might be a temporary denial of where you are or it may be that moment when you breathe deeply and clear your mind before all your previous fears come rushing back (and exactly when you open your mouth for the speech or try to sleep in the dark room that creaks and whispers).
Confidence is hard to find. To overcome a troubling situation you can't avoid, find your best state of denial (deny everyone in the room has hearing or that a dark room is exactly the same when the lights are turned back on). If you are an unconvincing liar, perhaps you can try writing a list of ten situations worse than the one you're about to be forced into. This is not confidence, it is making yourself miserable rather than nervous, but it does cure your first dilemma.
Maybe that's what confidence is, forgetting the dangers and fears of the moment.
It depends on the situation if this is wise or costly.
Confidence.