I will explain here how to set up Google authenticator for your WordPress website this is gonna enhance the security of your website significantly because you're going to need a second form of authentication are in order to access the backing of your site so you will need a username password and the unique randomly generated code is delivered to your smartphone this will make it much more difficult for people to access your website.

To achieve this I have a implemented this feature very simple way with open source PHP Google authenticator library, created a QR code in the dashboard widget to authenticate the Google authenticator app so that the app will generate authentication codes, also added setting at general settings section to enable or disable two factor authenticator at the login screen and added custom field at login screen to enter authentication code to verify.

For complete tutorial vist - http://scripthere.com/wordpress-two-factor-authentication-login-with-google-authenticator/