A Hard Reset reverts a phone to its original settings and a clean OS (Operating System) removing all data and information added to the cell phone by the mobile phone user.
In essence a Hard Reset erases everything from the phone and puts the phone back to like new condition as though it’s brand new right out of the box.
1. First lets turn off your device by holding down power button.
2. Now press and hold Power button, volume down and home button at the same time.
3. When you will see LG logo on your screen you can release those buttons.
4. Wait a moment and there should Hard reset menu on your screen.
5. Navigate with volume buttons to this wipe data/factory reset option and select it with Power button.
6. And it's done! the whole hard reset process is finished and your phone soon will be ready to work.