A reset may become necessary if your Apple iPhone 4, 4S or 3GS becomes locked up or frozen and isn’t responding. Here’s how to perform both a soft or hard reset.
1. Press and hold the Sleep/Wake button on the top of the unit until a red slider appears
2. Drag the slider on the screen.
3. Press and hold the Sleep/Wake button until the Apple logo appears.
Press and hold both the Sleep/Wake button and the Home button for about ten seconds, until the Apple logo appears.
Photo by montymetzger