Thread:Xavi3r3r/@comment-26633194-20150710143703/@comment-24577221-20150710160300

You can receive diamonds by adding friends to your friends list (assuming that you're running the mobile-device version of the game) or by getting people to add you to their lists.

You need to be careful not to advertise your friend code "inappropriately". People have lost their game accounts completely, with no warning, after they have spammed their friend codes. I don't know what BBB consider "inappropriate".