How to restart an iPhone without the ability to use the touch screen?

How do i restart an iPhone without the ability to use the touch screen?

Added (1). My dad's iPhone appears to have a touchscreen issue… The touchscreen is completely unresponsive, but the lock/unlock button & volume keys and the home button all still work. It looks like the glass screen got pushed too hard against the touch-sensitive layer behind it and it no longer responds, but I want to see if a restart will do anything for it before we have to pay for a warranty fix on it.

Hold down the lock/power button and the home button together until it turns off, then turn it back on

Hold the home and power buttons till it restarts