Ask HN: What’s your methods to ‘turn’ off your brain?

If you're a thinking person (a good thing!) then it may be impossible to create some sort of self-imposed coma.

However, if the goal is to stop thinking about one type of thing (work, a failure, an event) that can definitely be accomplished. When the thought is forming, immediately begin meditation. Retrain yourself to escape or dismiss the idea on command.

I close my eyes and listen to my surroundings until I can locate ten distinct source of noise and guess what are they. This usually brings a small but immediate detachment of problems and an attachment to the present.

Vipassana Meditation - see Mindfulness in Plain English.

I use headspace app. You should try it for a month and see.