To set a start up or shut down time, use these steps:
- 

- From the Apple () menu, choose System Preferences. 

- Click the Energy Saver icon in the window that appears 

- Click the Schedule button in the Energy Saver preferences window 

- Select (check) the option to start up or wake the computer, then set a corresponding time. 

- Select (check) the option to shut down or sleep the computer, then set a corresponding time. 

- Click OK to save your settings. 

Your computer must be awake at the time that it's scheduled to shut down, and remain awake for at least 10 minutes past the scheduled time, in order for it to shut down on its own. If your computer is sleeping at this time it will continue sleeping instead of shutting down. If you've set your computer to go to sleep after less than 15 minutes of inactivity, the computer may go back to sleep before it shuts down.
If you'd like your computer to shut down at a specified time (even if it is sleeping) and you don't need your computer to automatically start up later, you can schedule it to automatically start up 5 minutes before you've scheduled it to shut down.