Turn on System Preferences and press Mission control.
At the bottom left of Mission control will see "hot", press down will pop up to enable the screen hotspot list, inside? Four Corners four mouse hotspot function, open pull down menu There are many functional options, such as Mission Control, application window and so on, but we want to be " Start Screen saver ", you can set to one of four corners, for example I set to the upper left corner.
When you are done, the screen saver's mouse hotspot is complete. But if your Mac doesn't set a password, please enter the security and privacy settings password, please ensure that the "go to sleep or start screen saver wake up the computer needs to enter the password", and in the Drop-down menu select "Immediately", with the mouse hotspot lock machine function will be fully present.
Finally, drag the mouse to the upper left corner, or set your own corner to try it.
