When Facebook began in 2004, the popular social networking site was only accessible to college students at Ivy League universities. Five years later, Facebook comprises an active user base of more than 150 million people across dozens of countries worldwide.

What changed in those five years?

Well, for one, Facebook drastically expanded its user base. The site, once known for its exclusivity, has become accessible for practically anyone with a computer. In fact, while Facebook remains wildly popular among college students, the majority of Facebook’s new growth comes from users who are 30 years old or older.

While luring an older and more professional demographic has been a coup for the company, it has had a somewhat less desirable effect for many preexisting Facebook users. While photos of drunken shenanigans and crude 3:00AM wall postings have become the norm in Facebook’s college crowd, many users are now being forced to reconsider what they post on their walls. What if your boss is on Facebook? Or that nosy tattletale co-worker? Or, God forbid, your mother? Worse yet, what if they try and friend you???

Thankfully Sarah Perez, of the web technology blog ReadWriteWeb, recently contributed an article to NYTimes.com detailing the step by step process by which a user can filter their page using Facebook’s “Friend List” feature. We’ve copied the nuts and bolts part of Sarah’s advice below, but make sure to check out the full article for an interesting perspective on how much info is too much info for the modern Facebook user.

From the article:

To get started with Facebook Lists, you first need to build one. You can do this from your Friends page. (Click “Friends” in the blue bar at the top). On the left side of the page, click the button “Make a New List.” Give it a title.

Now you’ll have the option to add your friends to the list. You can either start typing in names one by one or click on “Select Multiple Friends” to add several people to the list all at once. (To add people, just click on their photos.) When you’re finished, click the “Save List” button at the bottom.

Once you have some lists created, it’s time to figure out who gets to see what. To edit your privacy settings, go to “Settings” at the top-right of the screen next to the search box. When you hover your mouse over the link, you’ll see a menu appear; click “Privacy Settings”on this menu. On the following page, click “Profile,” the top choice in the list of options.

On the profile privacy page, you have the option of customizing exactly who gets to see what. You can modify the following areas: Profile, Basic Info, Personal Info, Status Updates, Photos Tagged of You, Videos Tagged of You, Friends, Wall Posts, Education Info, and Work Info. If you’re unsure of what any of those things are, click the “?” next to the item to read a definition.

Using the drop-down boxes, you can customize who gets to see your info: “Only Friends,” “Friends of Friends,” or “My Network of Friends.” To lock down your profile to friends only, you could set all these to “only friends.” But since you have now created specialized lists, you’ll want to use these instead.

To do so, click the fourth option from the drop-down box: “Customize.” From here, you can add lists of people who should NOT be able to see this part of your profile. For example, if you wanted to block a list of work colleagues or those in your family from seeing your status updates, you could do so here – just type the name of your list in the box “Except these people” and save your changes.

Note: you can also block certain people individually just by typing in their names, but given the ever-growing number of Facebook users, you’re probably going to need a Friend List at some point. We recommend biting the bullet and creating your lists now instead of treating everyone as a one-off.

After you’ve saved your changes, you’re done. You’ll have your privacy back without having to change the way you and your friends use Facebook. Of course, keep in mind that nothing is foolproof – determined hackers can gain access to your account as can anyone who guesses your password….so maybe you shouldn’t use your dog’s name.

When lists are finally in place, you can assign new friends to a list right when you’re accepting their friend request – just look for the option “Add to Friend List” before you click “Accept.”