When you get to your home page on Google+, you will see options on the left side that you can choose from.
When you click on Start a Hangout, you are given an option to enable hangouts on air, if you select this, your hangout is no longer private, but allows you to broadcast your hangout on YouTube for an audience to see. You can see that a pop up making sure that you want this session to be broadcast and not private requires you to click your decision. You are also asked to name your hangout, maybe Author Visit with John Green or April Library Meeting.
As I presented this to the library coordinators at their monthly Region One meeting, I had the camera focused on them, so when they spoke, you would see them on the screen.