How Can I Open My Username And My File (I'm Star Username)?

Since your question is placed under "Using Blurtit" category, I would assume you are asking about your Blurtit username.
To open your username you need to visit www.blurtit.com/login.php. Provide in the username and password and your profile will open in front of you. After that click on "Edit my profile" words which are on your username display tab and Information tab.
Once you click on it different tabs will be displayed in front of you which includes:
Profile: Provides you "Edit user details", "Who Information Edit", "Edit Avatar" and "Adding New Pictures".
Friends: Shows list of your friends and adding/removing them.
Notifications: Provides you options regarding receiving blurtit notifications,
Privacy: Provides editing shoutbox and profile privacy options,
Account: Provides chnage Email and chnage password options.
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In case you forget your password and unable to log in, You need to use "Forget Password" option and your password will be provided to you on Email which you provided at time of registration.
Enjoy blurting!