1. First, enter the word "command" in the search box in the lower left corner of win 10, and a command prompt will pop up.
2. Then click the right mouse button and select the "Run as Administrator" option in the right-click menu.
3. Then enter the command "bcdedit /set testsigning on" at the command prompt, and then press Enter.
4. After restarting the computer, the watermark of "test mode" appears in the lower right corner of the computer desktop, and the test mode is successfully started.
5. In the same way, enter the command "bcdedit /set testsigning off" at the command prompt, and then press enter to restart the computer and close the test mode. After the above settings are completed, the test mode can be turned on and off in Win 10 system.