It’s a very simple and easy steps to know which wil not take much of your time. With the help of some pictures you are going to understand it better in an imaginative way.
1. The first you have to do make sure the device have good data connection or you can do this by activating the data .
2. Locate the device setting and select the icon
3. You are going to see a lot of option in the setting , select about device and click system update .
Note: This will cause data charge , make sure no interrupted power supply during this operation or else may cause critical damage for the device. Make sure the device batter is completely full.