I've learned that it is important to inform the students of who I am and why I am qualified to teach them.  It's also important for the students to get to know one another as well as for the instructor to have background information on each student so that the instructor can get an idea of what knowledge and experience each student brings to the class.

Ensure that the students as well as the instructor are familiar with the online learning platform.  The instructor needs to familiar with managing the course, that is, the class roster, assignments, etc.  Resources should be available to the students as they progress through the course and they need to be aware of how they will be evaluated.