“You’ll want to thoroughly familiarize yourself with the course you are going to teach, because if you don’t understand the content, approach, and principles of that course, you will find it hard to be an effective instructor,” Ko says. “Also find out what you can add or change in the course, whether that is your own commentary, additional resources, assignments, or discussion questions. Or it may be that your unique contribution will be in providing feedback and facilitating interaction in the class.”