If we are to imagine that all of our words, movements and actions create eternal imprint on this universe, and that everything we do sooner or later comes back to us in one form or another, then it seems very logical and indeed, the only possibility, that all we need to become a good person is to love everything and everybody starting with ourselves.
We all know what is good. All the qualities needed are present when we're born.
We just have to listen to ourselves. No matter what anybody tells us, we must do what makes sense to us, otherwise we're not living our own life.
We just have to listen to the peace that dwells within us. Sometimes to make non essential noise, that drowns the peace, go away we have to observe it, and gradually it will dissipate.
Obviously the answer to this question could be as long as life itself. So I'll finish with this: it is better to die for what you believe is good and right, then to do something that you know deep down is wrong and bad.