Recovery, in Android, refers to the bootable partition, in which the recovery console is installed.
It contains tools to help repair your installations as well as install official OS updates by using a combination of key presses or instructions from a command line sometimes.
Android is open, meaning the recovery source code is available, so that building a customized ROM is relatively easy.
1. At the start please press and hold Power button to switch off your device.
2. Next thing you have to do is to press and hold Volume down + Home + Power button.
3. When you will see LG logo on the screen, you can release the keys.
4. After few seconds you should see hard reset screen.
5. And this is it! to navigate in here use volume buttons and power button to select.