In order to change settings for the Broadcaster mini, you will first need to have it connected to Wi-Fi and paired to your account.
In the Livestream mobile app, go to Settings > Livestream Broadcaster and select your connected Broadcaster mini. A preview will open:
To change the event you are streaming to, tap the title at the top of the screen. A dropdown list of your events will appear. Tap the event you want to stream to.
On the main preview screen, tap the gearwheel in the upper right corner to enter settings.