Neti, neti translates to English as Not this, not that.
Dzogchen (“Great Perfection”, in Tibetan Buddhism) describes a constant, still presence that is our true nature. All the ways we establish a separate identity take us a step away from the experience of that presence. It’s difficult sometimes to answer the question “so what am I, if not that?” Our strong urge to establish an “I” that is separate from all-that-is keeps us from continuing to ask that question. Neti, neti is suggesting to us that as awareness notices an “I”-attachment, it is useful to find a way to let go of that attachment, to realize that it is not essential. We have so many layers, a fractal onion that keeps on going, can one continue to work on peeling off layers?
A regular meditation practice has helped me by giving the mind time engaged in a process towards quiet-ness, stillness. There is time to recognize and let go of the mind’s passion for holding attention on the thoughts that come to it. During the rest of one’s waking hours, awareness can be used to notice our automatic ways of re-acting that can be blind to aspects of “what is”, and once recognized can be more readily be dropped from one’s repertoire, to the benefit of all-that-we-are.