Do you agree or disagree with this statement? If so (or if not) why? Once you start to think about whether or not you think this is a true statement, you can expound upon your opinion and then use examples from the media (TV, movies, magazines, ads) to support your opinion. You could also look at it from an outside culture. For example, does the media in another country reflect that country's society accurately? From an outsider's viewpoint.
I hope this helps you get started!