If you go to your personal details section on their recruitment website you will see a tab saying personal details form.
Down the very bottom of this form is a tab saying
Are you a Virgin Blue Group "Blue Star"? (ie. Have you been referred by one of Virgin Blue Group's existing employees?)
You then add a staff member you know, you will need their start date at Virgin and their virgin email address etc.
Helps if you know management or a captain etc