Kingo-compactable devices : http://www.kingoapp.com/android-root/devices.htm
Kingo-ROOT download : http://www.kingoapp.com/index.htm
Step one: Download and install Kingo Android Root into the PC.
Step two: Enable USB debugging mode on your phone. If it’s running Android 4.0 or 4.1, tap Settings, Developer Options, then tick the box for “USB debugging.” (You may need to switch “Developer options” to On before you can do so.) On Android 4.2, tap Settings, About Phone, Developer Options, and then tick USB debugging.” Then tap OK to approve the setting change.
On Android 4.3 and later (and some versions of 4.2), tap Settings, About Phone, then scroll down to Build Number. Tap it seven times, at which point you should see the message, “You are now a developer!”
Step three: Run Android Root on your PC, then connect your phone via its USB cable. Make sure Device compactable USB driver installed,
Step four: Click Root and wait for couple of minutes to complete, including the automated reboot at the end.