1. First of all, turn the device off.
2. Next, hold down the Volume Up key for a while.
3. Keep holding the Volume Up button! Also, press and hold the Power key for 3 seconds, then release it.
4. After the tablet screen turns on, you can stop holding the buttons.
5. Cheers! You now should be in the desired mode.
6. You can navigate this mode by using the Volume buttons and confirm options by holding the Power key.