Two Step Verification or Twp Factor Authentication is much needed feature and it should be enabled for your Google account and all your exchanges where you keep your cryptos or day trade. as It will give you an ease of mind aswell
Gmail Account Two Factor Authentication
Enabling 2FA is easy on google , just open 2-Step Verification link and follow the steps given on the link.
Here you will need to install "Google Authenticator App" on your mobile and sync it with your account. the whole process is self explanatory
Two Factor Authentication for Exchanges
Different exchanges have different setting options but mostly generally fall under "security" of account.
For BTC-E go to Security > Two-Factor Authentication ( https://wex.nz/profile#security/2fa ) .
Poloniex hover your mouse over the wrench after logging in and click on Two-Factor Authentication (https://poloniex.com/2fa )
Back Up Code
While setting up 2FA you will see "Backup Code" do keep a copy of that so that incase of a corrupt or lost phone you are not locked out of your accounts...
For some reason while entering the 2FA code from your google authenticator code into a website while logging in and you find that the code is not working do not get alarmed and simply go to settings of your Google Authenticator App and click Settings > Time Correction for Codes > Sync Now. That will allow you to log in