Live for today, love for tomorrow, and laugh at all your yesterdays. Never regret the past, always hope for the future, and cherish every moment you have.
To live a life with no regrets a person has to be willing to take life for all that it be, and without expecting to understand or win every battle, but instead to just love life, period. No matter what you do, you will make mistakes, and that is okay. Nobody said that everything would come easily, and not everything that happens in your present will be completely understood.