Turn off your iPhone or iPad. (Hold down the Sleep/Wake button until Slide to power off appears, the slide.)
Plug your USB to Lightning cable (or USB to 30-pin Dock cable for older devices) into your computer.
Hold down—and keep holding down—the Home button on your iPhone or iPad.
Plug your USB to Lightning cable (or USB to 30-pin Dock cable for older devices) into your iPhone or iPad.
Continue holding down the Home button until the connect to iTunes screen comes up.