Follow these steps to protect your facebook account :
1- Log in to Facebook, then click Account.
It is located on the top right (next to Profile). Click Privacy Settings.
2- Decide how private you want your profile to be.
Click on each tab—everyone, friends of friends, friends only, recommended, and custom. Look at the dots for each one—the dot shows who can see that aspect.
3-Uncheck the "Let friends of people tagged in my photos and posts see them" box.
This ensures that only your friends are able to see posts and photos that you tag.
4- Click the Customize Settings link under the box you just unchecked.
This will allow you to further edit your Facebook settings.
5-Decide how private you want certain things to be by selecting from the drop-down menu.
6-Hide certain people or networks from seeing your information
To do so, click Customize from the drop down menu. Then, choose "Friends Only," uncheck any networks you don't want to see your photos (remember that when this is checked it means that anyone in the network can see that piece of information, not just your friends in the network), and type in the names of any person on your friends list you don't want to see your info.
7-Make a certain piece of information visible to only a couple people.
To do so, click Customize from the drop down menu. From the next drop down menu, choose Specific People...Then, type in the name of the people you want to be able to see the info. As long as your networks are unchecked, only those to whom you grant permission will be able to see that piece of information.
8-Change your photo privacy settings.
Click on Edit Privacy Settings for existing photo albums and videos at the bottom of the Things I Share section.
9-Choose the appropriate settings for each album
Use the drop down menu as you did for the previous steps. Click the Back to Settings button in the upper left corner when you are done.
10-Preview your profile.
This feature allows you to view your own profile as if you were someone else. It will help you make sure that they can only see what you want them to. To do so, click Preview My Profile in the upper right corner.
Type in the name of the person's view you want to check and press enter.
11- Click Back to Privacy Settings to make any necessary changes.
Then enjoy your newly secure Facebook profile!
hope this article be useful for you .
article source : http://www.wikihow.com/Protect-Your-Private-Information-on-Facebook