How to Enable Two-Factor Authentication on Gmail and Google

You can enable 2-Step Verification to your Google account by making some changes in your account settings.  Just follow the below steps to activate the most secure feature of Google for your Google Account.

1. Click here to go 2-Step Verification, Now click on Get Started. It will ask you to log in your Google account first to set up your phone as your second sign-in step.

2. Enter your Google account password, as you enter your Google account password; It will show you the device you are using to your Google account.

3. If your device is not listed there, Click on Don’t see your device? and it will popup a window with the instruction to get your device ready for 2-Step Verification. Once you are done with the steps. Your device will appear in the list.

4. As your device is listed there. You can tap or click on TRY IT NOW.

5. Once you click on TRY IT NOW, Google will Prompt a message on your device screen i.e Trying to Sign in? with the all the information regarding the Device, Location and Time.

6. Tap on YES on your mobile device to activate 2-Step Verification. Your login is approved message will appear on the device.

7. For further backup, Google will ask you for mobile number and method to get codeslike a Text message or Phone Call. You can select anyone.

8. After entering your mobile number click on Send. It will send a code to your mobile. Enter that code to confirm your mobile number with Google Account.

Source : http://www.tracingpage.com/blog/isp/how-to-setup-gmail-2-step-verification