adding facebook to my site

I have seen on other forum, that up the top where:
home, memberlist,profile,usergroups,messages,signout Is, people are also able to do the link to facebook, myspace etc etc, how can I do this on my forum??

Thanks for your help

Go to Display>Headers and navigation> scroll down to the bottom of the nav links box.
Click on Add customized menu.

Once you have the new nav. link made you can arrange the position of the button/link in the nav links box using the up/down arrows.