1. Good teachers are authentic.
Think about the teachers you most respected and admired. Think about the teachers that encouraged you to do your best work. Among other qualities, you would probably describe those teachers as authentic. They were true to themselves in their Teaching Role.
2. Are you more authentically Formal or Informal as a teacher?
How can you be authentic? Think about a continuum: on the one side, we have an extremely formal teacher, whose role emphasizes professionalism, expert knowledge, distance between student and teacher, clearly defined and specified goals and expectations…. on the other side of the continuum is a very informal teacher, whose role emphasizes casual relations, learning as exploring, cooperative teacher-student relations, and flexible or evolutionary goals and expectations. Where do you think that you would naturally fall on this continuum?
3. Your teaching role should be a conscious part of your teaching.
Where a teacher falls on the continuum of formal-informal varies. There is no right or wrong. Your preferred place on the continuum may even shift slightly over time, or according to context. As a TA, you should be aware of where you are on the continuum.
4. Your teaching role will interact with different teaching roles. Plan for this.
You also need to be aware of roughly where the Professor you work with falls on the continuum. For example, you may be a slightly more formal TA, working for a very informal professor. This combination will shape your job as a TA differently than if you were working with a professor who is more formal. As with any teamwork or working relationship, you should think about compatibility and complementarity of Teaching Roles, so that your experience, the professor's experience, and the students' experience of the course are as good as they can be.