The third practice is the oldest and the simplest. Every night you pass through a door between waking and sleep, and every night you pass through it asleep. This practice asks you to pass through it awake.
Lie down comfortably and let the body grow heavy. Do not fidget. The stillness is half the practice.
Then give the mind one thing to hold. The tradition of Gnosis teaches a sound for this: FARAON, said slowly and inwardly in three long syllables, with the R rolled. While you sound it, picture the great pyramids of Egypt at night. Let the sound carry you toward sleep.
Near the edge, the body becomes very heavy and the mind drowsy. Images may come, or sounds, a buzzing or a wave of vibration. Do not get excited, and do not watch for it. That is the door.
Now act without thinking. Feel yourself as light as a breath, and rise from the bed gently, the way a soul would rise. Then give a little jump, intending to float. If you float, you are out. If you land, you got up in the body. Lie down and begin again, without frustration.
It may take many nights. That is normal. Each night you practice, you pass the door a little more awake.