If you are going to sell your iPhone, or just want a fresh start, you will want to know how to erase all your content including passwords, apps, saved data and personal settings. Fortunately that is very easy to do. It’s always best to start by backing up though so you can have the content you are erasing available for your new iPhone or other iOS device. To do this, tap on Settings on the Home screen of your iPhone and then choose iCloud and then Storage & Backup.
After your backup is complete and before you erase the content on your iPhone, you will need to disable Find My iPhone if you have that enabled. You can do this by tapping on Settings, iCloud and then Find My iPhone.
Finally you will be ready to erase all the personal data on your iPhone. To do this, tap on Settings on the Home screen of your iPhone and then tap on General. Once you are in General, scroll down until you see Reset and then tap on this. From this point a number of options will come up and you will see Erase All Content. Tap on that and then tap to confirm your selection to Erase iPhone. You will be prompted a second time just to make sure it’s what you really want to do, so tap Erase iPhone again.
After you have tapped on Erase iPhone all of your content will be erased.