Carpe Diem.

You are guaranteed nothing in this life, especially a tomorrow. Take what you can from today to ensure that no moment passes by wasted. That doesn't mean you should live selfishly and only for yourself, but that you should live each moment to its fullest extent. Go skydiving, compete in a triathlon, volunteer for a charity, learn to box. Your life is never going to be anything more than what you make it, go make it something great.