If you want to broadcast, you should have a listen2myradio account. If you don't have it, go to the listen2myradio website and create an account. After you finished creating the account, go to the VDJ broadcast config panel and enter the details of your account. Then select Broadcast to a radio server, click Start Broadcast and press the Play button on the deck that you want to start your broadcast.
Shown below is the panel where you should configure the broadcast settings:
For more detailed information please consult page 59 in the VDJ manual.