“How do we keep clear light wisdom realization in our minds? Simple! Practice Dzogchen meditation. Look to your mind. When you look to your mind and ask, “Where is my mind?” you’re not going to find anything. Dzogchen practitioners must constantly observe their minds with great precision. Be aware at all times. Look directly at your mind, instantly, immediately, and directly. In that moment of looking, you don’t find anything. As the Buddha said, “Not finding is the supreme finding.” So enjoy and relax in that state. By stabilizing your recognition of the true nature you are “nailing down” the “clear light unimpeded wisdom” beyond subject, object and action. Abiding in that state is “driving the nail of clear light unimpeded rigpa at the juncture of samsara and nirvana.”

The great Dzogchen master Longchenpa gave this advice:

On a comfortable cushion, relax your body with your spine straight. Don’t recollect past memories and don’t provoke future plans. Settle your mind in the instantaneous present. Smile and enjoy the fresh, radiant tranquility that you begin to experience by allowing this to shine.

When you relax in the fresh, instant moment you begin to experience the “unimpeded clear light wisdom nail of rigpa.”

Venerable Khenpo Rinpoches
The Seven Nails: The Final Testament of the Great Dzogchen Master Shri Singha (pgs 94-95)

Seven Nails: The Final Testament of the Great Dzogchen Master Shri Singha