To set Google 2FA first you should login into your account.
Then go to My Account menu and choose "Security"
Then you will be directed to My Security Page. On this page you can change "Security Notifications" and "Google Authenticator".
Go on Google Authenticator and hit "Enable 2FA". When you click on it, you will recieve an email in which you should authorize Two Factor Authentication Request.
Go to your email and hit "authorize".
Please note that this email is valid until five minutes and after that would be expired. If you couldn't manage it before expiration time you should do the process over again.
After you authorize the action you will back to the "User Profile Setting Page". Then you will see a QR Code and a Secret Code. (Following photo)
The Secret code is a sixteen - string of numbers and English Alphabet. Write down the Secret Code on a paper (avoid of storing digitally) and put it somewhere safe. In the future if you can't access to your phone and need too set 2FA on a new phone you will need it. Otherwise you can't access to your account.
Please note that if you enable 2FA you are required to enter a code on each login.
Then open Google Authenticator application on your smart phone. You can download it from Google Play or App Store.
On the application hit on + button and choose:
Then trigger your camera into the barcode. The SynchroBit will be added in a few seconds.
Every sixty seconds a new six digit code is being generated.
Then enter the code on "Enter Token" and click validate.
After that a message is being showed as:
You are all set.