Next time you can't fall asleep, try cognitive shuffling: https://www.bbc.com/future/article/20260311-cognitive-shuffling-the-micro-dreaming-technique-that-helps-your-brain-to-rest

BBC
Cognitive shuffling: The micro-dreaming game that helps you sleepFor over a decade, this image-based technique has helped people switch off their busy brains and fall asleep at night. How exactly does it play upon the mind?