1. Open the battery slot on the back and put on 3 AA batteries to turn on the switch. 2. Place your hand in the lie detector to make sure each finger can touch the sensor. 3. Press the button to hear sound current/rattle indicating the current mode. 4. Press the polygraph to start the polygraph 5. Every time you answer the question, the polygraph measures your answer the lie index. Screaming and shocks and strenuous You can feel the bites of your fingers