If You're Seeking Shut-Eye Limit your caffeine use, including coffee, tea, soda, iced tea and chocolate. Exercise, but do so at least five or six hours before bedtime. Limit alcohol and cigarette use. Stop both at least three hours before bedtime because they can disrupt your sleep. Don't lay in bed awake. "Don't look at your clock all night. When you first notice that you're just laying there, and you start to feel frustrated that you can't sleep, get up and go do something relaxing in dim light," she advised. Only use your bed for sleep and sex. Don't watch TV in bed. Keep the same bedtime and awakening time seven days a week. Harris said that most adults need between seven and nine hours of sleep a night. How do you know if you're getting enough sleep? "If you're sleeping well throughout the night and you wake up feeling refreshed, you're at the right number of hours," she said.