First, click on Manager, then click on My Groups.
Next, click on the name of the Group that you want to add a user to.
Lastly, click on the Add User button. This will bring up a form that you can use to add the user. The Email field is checked first -- if a user with that email already exists in the platform, then that user is simply added to the group. If the user does not exist, an account will be created using the information that you entered, then they will be enrolled in the group. A user that is added to a Group will automatically be enrolled in all of the Courses that are assigned to the Group.