came across this rule

So the 10-3-2-1 method is as follows:

• 10 hours before bed: No more caffeine.
• 3 hours before bed: No more food or alcohol.
• 2 hours before bed: No more work.
• 1 hour before bed: No more screen time (shut off all phones, TVs and computers).
• 0: The number of times you'll need to hit snooze in the AM.