When a friend you invited joins WriterBabu through your link, you earn one-fifth( 20 percent) of their reputation till their score cross 500.
You can invite friends here: http://www.writerbabu.com/invite_friends.php
You just need to enter the email address of your friend(s) and click on the send invite button. Your friends will very shortly receive an email invitation stating your name. Once they click the link provided in that email, they will be taken to the signup page where they have to enter their name and a password, that will complete their registration. Now once your friend is on WriterBabu and they earn reputation, their one-fifth of score will get added to yours. You also earn badges on inviting friends to WriterBabu. Checkout badges here: http://www.writerbabu.com/badge.php