Regardless of how you setup your Google Hangout ( see this document) this tutorial will walk you through the process of inviting guest and running the Hangout.
The first thing you will want to do is invite people to join your Hangout. On the initial screen you will see a box where you can invite individuals:
You can enter names (from you contact list), emails or if you have any circles setup you can invite entire groups with a single click:
- Once you have added the information hit “Submit” and Hangouts will send out an invite to the people you entered. If they have a Google+ account they will see the invite notification in the box next to their name on either their Google+ page or the Gmail page:
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They receive an email containing the join Hangout link:
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This is the main Hangout Screen:
The bar in the upper right hand corner shows: audio input level, mute mic button, mute video button, connection speed, settings, and hang-up
The settings allows you to select your video input device, your audio input device, and your audio output device:
Below the main screen are your other options for the viewing on the main screen. To select a different main screen option simply click on what you wish to view.
Along the left side of the Hangout screen you will see a number of Hangout activities:
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Invite Others: Used to add additional people to the Hangout
Chat: Online chat feature
Screenshare: Share your desktop or specific window with the group
Capture: Grabs a screenshot of the hangout
Google Drive: Allows you to access documents on your Google drive to share - You can also click this to create a shared document (with all Hangout attendees) to take notes.
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YouTube: Allows you to share YouTube videos
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allows you to invite additional people 
, select your camera, mic, and speakers , and access a few additional tools 
We talked about adding people to your Hangout above.
The gear icon 
allows you to select your camera, mic, and speakers.
The three dots give you access to a few additional Hangout tools and helps.
As you see you can access the chat feature from here or you can click on the chat icon 
in the lower left corner of the screen.
From here you can send a chat to the entire group in the Hangout. You can also show or hide the chat window from here.
The three icons at the bottom center of your screen are to mute your mic or camera and to hang up the call.
