It's the end of your day and you're about to fall asleep. Your day was amazing, sad, exiting disaponting or whatever. You still think about what you should have done or what you could have done better. You're not satisfied about something you can not change anymore, you're just blowing your minds with things that belongs to the past. Indeed, thinking about it will just put more anxiety or anger in your body so you're just destroying yourself.
Just imagine that before you close your eyes you would be thankful to life, to thank life for this day that has ended, because whatever happened it's the best you've got! If you stop thinking about the fact of the previous day, you will enjoy the new one. Actually, every day is a new day and it's up to you to take the opportunities from it. No need to blame yourself and worried about the irreversible.
Thank life for your day and close your eyes.