With an **invitation** of course! 1) Make sure you're on the **group page** that you want to invite people to. 2) On the right side of the screen, under **"Members,"** click on **"Invite User."** 3) Enter the person's **email address** (separate multiple email address with a comma). 4) Set their role, a **viewer** can only see tracks, a **member** can edit and add tracks, and a **moderator** has all the same power that you, the group owner has. 5) Add a **personal message** so the person knows why they're being invited to your group. 6) **Send** the invitation! 7) When they respond, they're in, **that's it!** http://www.youtube.com/watchv=JBd69Rx6xRI

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