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How to sleep without using a bed
Find a place to lie down or sit in a relaxed posture.
It can be hard to get comfortable to sleep when you don't have a bed to lie down in (at the airport, for instance). Sometimes there is simply no feasible place to lie down, so you may have to opt for a chair or sitting against a wall.
If possible recline at a 135-degree angle for the most comfort. Avoid sleeping sitting straight up or leaning forward because this may cause undue pressure on your back and neck and it may also contribute to pain in those areas.