If you struggle sleeping don't count sheep (has that ever worked?). Count your blessings. What made you happy during the day? What are you grateful for in general? what are you proud of? No matter how bad the day may have been, this exercise allows you to go to sleep happy.
*Bonus. Before you sleep leave your subconscious with a tough question, you'd like the answer to. You'd be surprised how often you wake up with an answer.