For one week, work at being on time for all events. Consider what "being on time" means to you and to others. Watch what prevents you from being on time, and what arises in the mind when you or other people are late. (If you are a person who is always on time, you might try being a few minutes late and see what happens, externally and internally.)

Jan Chozen Bays in How to Train a Wild Elephant and Other Adventures in Mindfulness