This is a short guide to help those who may struggle with this fill in their networking details.
To begin with click your username within the welcome box, for example Hey, Kerry
Inbox: this will take you to your page.
Now click on the About Me tab.
Scroll to the bottom of the page and look for Social Networking ID's.
For Twitter you enter whatever comes after http://twitter.com/
of your Twitter profile URL.
For Myspace you enter whatever comes after http://www.myspace.com/
of your Myspace profile URL.
For Youtube you enter whatever comes after http://www.youtube.com/
of your Youtube profile URL.
For Facebook you whatever comes after http://www.facebook.com/
when viewing your own profile. For example if your profile URL is http://www.facebook.com/facebook-person/
you would simply enter facebook-person.
To get your Facebook URL login to Facebook, click on your name at the top left and copy all that comes after facebook.com/ from the URL you see in the address bar.
Hope this helps and if you have any more questions please seek support here