If you wish to Hard reset your phone, begin holding the Power key and select Power off once you see the option to.
Wait for the device to fully power off and after it has, hold the Power key and Volume Up together till you see the logo of the device on the screen.
In a moment, you will see the Recovery mode. In this mode, you want to use Volume keys to navigate in order to select Wipe data/factory reset and then confirm the selection with the Power key.
Once more affirm the process by selecting Yes in the same way as before.
Your phone should now start removing all personal data and when it's finished you will be greeted by the Android setup screen.
