Google Authenticator is a great tool to enhance the security of your account. In order to enable 2-factor authentication, you can visit your “My Personal Data → Security” page: scan the QR code or set manually the “secret code” to add your The Rock account to your Google Authenticator / Authy app***, then insert the code provided from the app.
***Remember: you should back up your unique code, displayed before enabling 2-factor authentication; through this code, you will be able to gain access to your account even in the case of loss/theft of your 2-factor authentication device.