You may need to press both buttons for as long as 20 seconds, so be patient! To do this, hold down the Sleep/Wake button (the power button) and the Home button at the same time. Press and hold these two buttons together until the Apple logo appears on your iPhone’s display. Pro tip: If you see the “slide to power off” wording on your screen, but your screen won’t respond, try some of the tricks from my article about what to do when your iPhone touch screen isn’t working. If it doesn’t, and you’re scratching your head, keep reading. Release the button or buttons when slide to power off appears on the screen. That’s your cue to touch the red power icon and swipe it with your finger from the left to the right side of the screen. Ideally, your iPhone will turn off when you do this. If you have an iPhone without a Home button, press and hold the side button and either volume button simultaneously.
To turn off your iPhone, press and hold down the Sleep / Wake button (what most people refer to as the power button).