Open the Health app on your iPhone
Tap Browse
Tap Sleep
Follow the on-screen setup steps to enable Sleep tracking
Set your Sleep Schedule
Set your Wind Down and Bedtime/Wake options
Put on your Apple Watch before going to bed
Ensure your Apple Watch is charged and worn snugly on your wrist
In the Sleep section, turn on Track Sleep with Apple Watch
Use the Sleep Focus if you want sleep mode automatically during your schedule
Review Sleep results in the Health app under Sleep (including trends and stages, if available)