The only way to know yourself is to sit with yourself; asking yourself questions, revealing everything, baring every feeling, and asking for understanding.
The obvious is that this helps you know yourself because you reveal yourself to yourself. The less obvious is that through this process you lose something very crucial, your need to know things about yourself that you don’t know. To paraphrase Don DeLillo, “What you don’t know about yourself allows you to know yourself.”
In Point Omega, in that specific sentence, Don warns against thorough self-examination because it satisfies curiosity about self. It strips the well. He warns that you will dive into the dark well that is yourself and hit bottom. That you will be pleased, but only for a moment, and then you will be utterly bored. That you will reach a point where you realize that what you have is the presence of what you wish to have. That you will one day look at yourself with great curiosity and find yourself devoid of curiosities. That you will consequently be left with, not curiosity, but a great reach for it.
I am for thorough self-examination for the exact same horrible reason. For in your utter boredom and extraordinary wanting you will leave the dark well, revisit it, leave it, revisit it, leave it, and revisit it again to sit down and examine the grounds. The whole process sounds like a waste of time (it is) and you will not know why exactly you’ve chosen to examine the grounds of the well now, but you will reach a point where, driven completely mad by boredom and by how boring you are, you eventually do just this.
After enough time sitting in the well like a lunatic, monotonously examining the dull grounds on which you sit on, you will find a crack. And in the ensuing frenzy of having finally found something fascinating, something that relieves your boredom, something that requires your attention, you will pick at said crack. And as you pick it will spread to consume the whole grounds on which you sit on until they give out from beneath you to reveal that the dark well went so much deeper. And you will swell with an almost forgotten curiosity, there are a great many things you don’t know about yourself! And you will ask yourself questions.
That is, in essence, the art of sitting with yourself to know yourself; you ask yourself questions, reveal everything, bare every feeling, ask for understanding, and continue sitting with yourself until you are psychotic enough to break through your own crude barriers.