To find out how long it really takes to lock down one's Facebook profile, I decided to practice on my own account: for every security choice, I picked the most limiting setting, granting access to the narrowest possible group of people. It took me a long, arduous... two and a half minutes.
Even with the fifty-plus options that Facebook offers, it is actually pretty easy to put your account on total lockdown. Basically, all you need to do is open the "Privacy Settings" page, which is available through the "account" tab on the top right of your Facebook screen. The privacy page has six options; simply go to each page and choose how much access you want to grant the outside world. For total lockdown, you click on "Only Friends" whenever possible, and uncheck all other options. For a step-by-step explanation, check out our video or this article on The Business Insider.