Live life fully while you're here. Experience everything. Take care of yourself and your friends. Have fun, be crazy, be weird. Go out and screw up! You're going to anyway, so you might as well enjoy the process. Take the opportunity to learn from your mistakes: find the cause of your problem and eliminate it. Don't try to be perfect; just be an excellent example of being human.
Men always talk about the most important things to perfect strangers. In the perfect stranger we perceive man himself the image of a God is not disguised by resemblances to an uncle or doubts of wisdom of a mustache.