In response to growing concern about privacy issues, Facebook recently rolled out some new and fairly complicated privacy settings. As critics point out, though, the default settings are pretty liberal, allowing quite a few people (including marketers) to see a whole lot more than you might like. And though you can put substantial restrictions on who sees what, the steps you take to do this may not be readily apparent.
In order to make the best of the new settings, you might try reading some of the guides put together by people who have done the hard work of figure this out for the rest of us.
10 New Privacy Setting Every Facebook User Should Know
How to Fix Facebook's New Privacy Settings
How to Hide your Facebook Friends List
Five Tips to Manage Facebook Privacy Settings