Click the "My Classroom" Link in the top toolbar.
From there, you will see a "Sample Classroom TO CLONE" listed. Click on that link, and then, in "author tools" click "clone." DO NOT CHOOSE EDIT.
All of the settings in the classroom are our default settings, and don't generally need to be changed. Merely, change the "Group name" (the title of the classroom) and "Description" to something that identifies your particular class.
You will also want to change the "welcome message" to something specific to your own class. When that's done, scroll to the bottom, and "save."
Your classroom now exists in the "My Classroom" area, and students can be added to it. In the next two videos you'll learn to set up your Tag Vocabulary, and how to import your students into your class.
Setting up your tags is easy enough -- you may want to do it right now -- simply click "tags" while you're in your classroom and you will see a link that says "edit vocabulary." Click that link, scroll to the bottom of that page, and click the last two check boxes -- "users can add tags" and "show user added tags."