How to use the online timer
Twenty minutes gives a sleep-focused meditation enough room to properly slow the body down — long enough to move past the restless, mind-still-racing first few minutes that almost everyone experiences when trying to wind down, without running so long that it becomes another thing to feel behind on. This is different to a daytime mindfulness session, since the explicit goal here is drowsiness rather than alert awareness.
Lying down rather than sitting upright suits this particular use better than most other meditation styles, since the aim is to drift toward sleep rather than stay sharply alert. Dimming lights and setting the room temperature on the cooler side beforehand supports what the meditation itself is trying to do, rather than working against it.
It's genuinely fine, and actually the point, to fall asleep partway through rather than finishing the full twenty minutes awake — unlike most other timed practices, this is one where not "completing" it is often the sign it worked. If a wandering mind keeps pulling attention away from the practice, gently returning to slow, steady breathing rather than getting frustrated with the distraction tends to work better than fighting it.
Common questions
Is it okay to fall asleep before the twenty minutes finishes?
Yes, that's actually the intended outcome for this kind of practice, unlike most other timed sessions where finishing the full duration is the goal.
Should I sit up or lie down for this kind of meditation?
Lying down generally suits a sleep-focused practice better, since the goal is to drift toward sleep rather than stay alert.