Instructions

1

Press the "On/Off-Sleep/Wake" button and hold it for a few seconds until a red slider appears, then press the "Home" button until a frozen application quits.
2

Press the "On/Off-Sleep/Wake" button and hold it until a red slider appears in the display, if pressing the "Home" button in Step 1 didn't resolve the problem. Slide a finger across the slider to turn off the iPhone. Press the "On/Off-Sleep/Wake" button and hold it until the Apple logo appears in the display to restart the phone.
3

Press the "On/Off-Sleep/Wake" button and the "Home" button simultaneously if Step 2 didn't fix the problem. Hold the buttons for at least 10 seconds, until the Apple logo appears in the display. The iPhone is now reset.