Restart your iphone 8 or earlier or ipod touch. press and hold the top (or side) button until the slider appears. drag the slider to turn your device completely off. * after your device turns off, press and hold the top (or side) button again until you see the apple logo.. Now you know how to hard reset your iphone 6s and iphone 6s plus. this works with older iphones as well, just that in case of iphones prior to iphone 6 and iphone 6 plus, the sleep/wake (power) button was on the top right corner.. Hard reset apple iphone 6s second method: plug in your iphone to the computer and open itunes.; next select your iphone from the left menu in itunes. click the restore button in itunes. * you can now do back up your files, just if you want.. How to fix white screen of death on iphone 7/6s/6/5s