First, train in the preliminaries.
The preliminaries are also known as the four reminders. In your daily life, try to: (1) Maintain an awareness of the preciousness of human life, (2) Be aware of the reality that life ends; death comes for everyone. (3) Recall that whatever you do, whether virtuous or not, has a result; what goes around comes around. (4) Contemplate that as long as you are too focused on self-importance and too caught up in thinking about how you are good or bad, you will suffer. Obsessing about getting what you want and avoiding what you don't want does not result in happiness.
[...from The Compassion Box by Pema Chodron, lojong card No. 1]