1. Personality: Great teachers tend to be good-natured and approachable, as opposed to sour or foreboding; professional without being aloof; funny (even if they’re not stand-up comedians), perhaps because they don’t take themselves or their subject matter too seriously; demanding without being unkind; comfortable in their own skin (without being in love with the sound of their own voices); natural (they make teaching look easy even though we all know it isn’t); and tremendously creative, and always willing to entertain new ideas or try new things, sometimes even on the fly.
2. Presence: The best teachers, as Lang concluded, are always "present" — fully in the moment, connecting with both their subject matter and their students.
3. Preparation: To be a powerful teacher you must go into every single class meeting as prepared as you can be, given the time you have. That means more than just reviewing your notes or PowerPoint slides. It involves constantly reassessing what you do in the classroom, abandoning those strategies that haven’t proved effective, or are just outdated, and trying new ones. It means being so familiar with your subject matter that you can talk about it off the cuff.
4. Passion: Passion, or love, manifests itself in the classroom in two ways: love for students and love for your subject matter.
As noted in the article, these four properties are always a work in progress. It may be hard to work on your personality (it can be done!), but presence and preparation are undoubted areas where you can continue to build your skill set. Passion may ebb and flow over the course of a career, but it's important to try and keep it up and express it to your students.