Place display on your arm.
The screen will be white throughout the session.
Each session is completely silent.
Wait until you feel the vibration signalling the end of the session.
If you are not sure if the session has ended, please look at the counter at the top of the screen to see how much time remains.
If necessary you can repeat each app consecutively 2 or 3 times depending on your sensitivity.
Can be repeated whenever necessary.