Seneca offers a nice discussion of this activity in his treatise On Anger:
“Anger will cease and become more controllable if it finds that it must appear before a judge every day. Can anything be more excellent than this practice of thoroughly sifting the whole day? And how delightful the sleep that follows this self-examination—how tranquil it is, how deep and untroubled, when the soul has either praised or admonished itself, and when this secret examiner and critic of self has given report of its own character! I avail myself of this privilege, and every day I plead my cause before the bar of self. When the light has been removed from sight, and my wife, long aware of my habit, has become silent, I scan the whole of my day and retrace all my deeds and words. I conceal nothing from myself, I omit nothing. For why should I shrink from any of my mistakes, when I may commune thus with myself?”On Anger (De Ira), book III, chapter 36 (trans. John Basore, Loeb Classical Library)
Of course, the benefits of this activity can apply not only to anger, but to other intense emotional states, and to many other parts of our intellectual, spiritual, and ethical lives.
As the last thing you do before falling asleep in the evening, recall the events and choices of the day, starting with the moment you got into bed, and continuing in reverse order from the end of the day to the beginning. As you go, note the places where events were outside your control, and the places where you had the opportunity to make choices about what to think, say, or do. Don’t worry if you fall asleep; just go as far back as you can, until you doze off.
Once you have been doing this for a while, you may find patterns emerging in the way that you often respond (or fail to respond) to certain people, events, feelings, places, or situations. Make note of these situations, and consider using them as starting points for the premeditation activity. Pay attention to which parts of your day are within your control, and which parts are not. With practice, you may find yourself with a greater ability to note challenging situations at the moment they arise, so that you can respond from a place of freedom, rather than habit or compulsion.
While it’s helpful to note which parts of your day were good or bad, pleasant or unpleasant, conducive to flourishing (eudaimonia) or not, try not to get caught up in praising or blaming yourself. (This is subtly, but importantly, different from the emphasis that Seneca gives in the quote above. He was writing prior to the neuroses that can arise from self-flagellation by “sinners in the hands of an angry God.” In his time and place, the concern was people who were too uncritical, not people who were over-critical.) Instead, focus on observing the patterns of your life, so that you can keep hold of the patterns which serve you well, and change the ones which do not. Once they are done, past actions are no longer under our control; but what is under our control is how we intend to act in the future.