Use a screen saver on your Mac
You can use a screen saver to hide the desktop when you’re away from your Mac or if you need extra privacy.
Customize the screen saver on your Mac
On your Mac, choose Apple menu > System Settings, then click Screen Saver in the sidebar. (You may need to scroll down.)
Click a screen saver thumbnail on the right, click Options, then adjust the settings.
The options available vary depending on the screen saver you select.
Source: Click the pop-up menu, then choose the pictures to show in the screen saver. You can use pictures that come with macOS or choose pictures from a folder or your Photo Library.
The top thumbnail shows how the screen saver will look. To check how the screen saver looks full screen, click Preview. To stop the screen saver and return to the settings, move the pointer.
Shuffle slide order: Show pictures in a random order instead of their order in the source.
Other screen saver options: Set options for color, speed, and more.
To show the time in the screen saver, turn on “Show with clock.”
Start or stop the screen saver on your Mac
The screen saver automatically starts whenever your Mac sits idle for the amount of time you choose in Screen Saver settings.
To change how long your Mac can be inactive before the screen saver starts, choose Apple menu > System Settings, then click Lock Screen in the sidebar and choose settings on the right. (You may need to scroll down.) See Change Lock Screen settings.
If you set up a hot corner for the screen saver, move the pointer over the corner to immediately start the screen saver. See Use hot corners.
To stop the screen saver and show the desktop, press any key, move the mouse, or touch the trackpad.
If you want more security when you stop the screen saver, see Require a password after waking your Mac.