Yoga nidra

Lying still for forty minutes without falling asleep is harder than it sounds.

Find a recording in your own language, thirty to forty minutes long — search for «yoga nidra» plus «full practice», or by a teacher whose voice you can stand for that long. Lie on your back on the floor or a mat, not on the bed, put something under your knees and head, and cover yourself: a body that does not move gets cold. Headphones on, lights low, phone in flight mode. Then simply do what the voice says — the rotation through the body, the counted breaths, the images — without judging whether it is interesting. There is one task: do not fall asleep. If you drift, open your eyes a little or move your fingers and come back to the voice.

What do I usually call rest, and do I actually rest while doing it?