Existing accounts:
When you are logged in to MovieStarPlanet2, click on Game Options (the cogwheel), and then My Account
New accounts:
Note that Guest accounts cannot use this feature. You need to register your username/account and create a password before you can add your email. Once you have chosen your password, simply follow the steps described above.
If you are under 13:
All you need to know about the Parental Control Center you can find in the articles below:
What is the Parental Control Center?