The fastest way to lock or sleep your screen in macOS

The fastest way to lock or sleep your screen in macOS

3. Set up a hot corner

Hot corners allow you to drag to the mouse pointer to one of the four corners of the screen to initiate an action – you can use one as a sleep shortcut on your Mac. To set it up:

1. Launch System Preferences.
2. Choose the Desktop & Screen Saver pane. 
3. Click the Hot Corners button at the bottom right of the window. 
4. In the drop down window, choose a corner.
5.  Click on the menu and choose either Start Screen Saver or Put Display to Sleep.

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