To get started broadcasting you must create your first channel. If this is not done for you already this is how you create you a channel if you are a reseller this is how you create additional channel for your account.
Click on the Live Channels side menu item and then select Add Live Channel
Enter a name for your channel and select the features you would like to enable.
The bitrate can be left as default, or you can specify a limit for this channel if desired.