How to Lock a Mac Computer

Using the Keychain Shortcut

1. 
   Go to Finder. Do so by clicking on the dark and light blue, square icon that contains a smiley face, or by clicking on the background image on your desktop.
2. 
   Click on Go. It's in the menu bar at the top-left part of the screen.
3. 
   Click on Utilities. It's near the bottom of the drop-down menu.
4. 
   Scroll down and double-click on Keychain Access. It's next to a keychain icon.
5. 
   Click on Keychain Access. It's in the menu bar in the top-left corner of the screen.
6. 
   Click on Preferences. It's near the top of the drop-down menu.
7. 
   Click on General. It's a tab at the top of the dialog box.
8. 
   Check "Show keychain status in menu bar." It's near the top of the dialog box.

   1. A padlock icon will appear on the right side of the menu bar at the top of the screen.
9. 
   Click on the padlock icon. It's on the right side of the menu bar at the top of the screen.
10. 
    Click on Lock Screen. It's at the top of the drop-down menu. The screen will go to sleep, and you'll have to enter your log-in password to access your Mac.

    1. Use this shortcut anytime you want to quickly lock your Mac.