Dzogchen is about resting in the “primordial state of pure awareness”. The term also derives from the “highest perfection” of the Vajrayana practice after the visualization of the deity and the mantra recitation is dissolved and one rests in the natural state of luminous and pure awareness.
There exist three series of Dzogchen teachings: the Mind Series (semde), the Space Series (longde), and the Secret Instruction Series (mangagde).
The Mind Series (semde) focuses on contemplation, or the Nature of Mind. The principal method employed is Zhine, or fixating the mind on a single object of meditation, at first on a visual object, and later on an empty location in space. The emphasis is on Kadag, or the primordial purity – also called Tregcho, the total relaxation of body, speech, and mind.
The Space Series (longde) focuses on sky meditation.
The Secret Instruction Series (mangagde) assumes one knows how to get into contemplation through different means. The emphasis is on Lhundrub, the spontaneous visible manifestations of energies potential within the Nature of Mind.
The three tregcho guidelines for meditation are: resting one’s mind in dharmadhatu (semde), resting effortlessly (longde), and resting without accepting or rejecting (mangagde).
The dzogchen talks about the eyes as the gates of wisdom. If there is a direct simplicity of mind, or tregcho, the light chains begin to stay and wait for your perception. In order to observe the vajra chains, you first have to develop a sense of carelessness at the dzogchen level; otherwise, they will not stop. When you have developed carelessness, noncaring, and spaciousness, they begin to slow down. If you have not cut through, you cannot see these visions. The more you cut through, the more these chains wait for you or actually come back to you. It is connected with the physical setup and speed of the brain. With this practice, you can actually see your own brain.