To look and perform your best, academic and image experts recommend a two-minute power pose before any stressful situation. During the event, keep an expansive posture with your chest open, but not puffed, and keep your head level or slightly raised.
In neuro this semester, we covered emotions and one theory of their formation is that a person feels something subconsciously, then physically reacts to it (for example, by frowning or smiling) and then consciously perceives the emotion. Just in time for my neuro final is an article about how standing confidently can increase confidence. Now I need to remember to strike a powerful pose before the best!