If I had such an opportunity, I would tell myself to re-evaluate my outlook on life. Do what you feel is right for you and not what is expected of you. I would also encourage myself to read even more than I currently did, because most knowledge learned is not gained from being in a classroom, and to keep an open mind of everything that surrounds you. Make myself understand that everything in this world is connected, one way or another, and to take the time to realize who your true friends are. Equally as important, I would teach myself how not to focus on material items and walk your own path, keeping your strays to a minimum. Appreciate the beauty, that is nature, surrounding you. Alter your diet. Write down your most abstract thoughts and strongest dreams. But, most importantly, let your goal in this life be one of knowledge, self-discovery, and inner peace.