Instructions to pin screen on AOSD devices

How to protect your privacy when lending a AOSD smartphone or tablet to someone else. Instructions for setting up "screen pinning" on a AOSD brand device. Block an application on the screen from which the user will not be able to exit without knowing the unlock pin, in this way you will prevent them from seeing your messages, photos and private data that you do not want to show.

AOSD S8 plus AOSD S8 plus
AOSD Q55 AOSD Q55
AOSD Q33 AOSD Q33