ALWAYS REMEMBER YOUR ABC'S

Always be cool.  It's as simple and as complicated as that.  I don't necessarily mean be cool in the high school sense of the word.  I mean maintain your composure.  Don't get flustered, don't act overly excited or uninterested in anything, don't speak too strongly about a given subject or situation.  Just be cool, not a cocky ass, but cool.  When in doubt, remember your ABC's.