The first thing I thought of was that the TA needs to communicate well with the teacher or professor. There needs to be trust and autonomy both ways. A good TA understands the professor's expectations and can explain them to students. Students need to trust the TA to get them through the course, and the professor needs to trust the TA to get the students the information they need, and grade papers correctly.
Teaching assistants are important keys to student success in many college classes, especially when lectures contain a large number of students. The teaching assistant should be a more accessible resource for students, a connection to the knowledge and expectations of the professor, but also a dynamic source of support for students in his or her own right. Since professors are often unavailable or slow to respond to a plethora of undergraduate questions, the teaching assistant needs to be able to quickly field questions, reteach or supplement material covered in lecture, and set up opportunities for students to explore ideas further. Many college students feel lost in big lecture scenarios, but a great TA can set a student up for success in further study.
Luckily, technology provides a large selection of communication methods for college students and teaching assistants, both of whom are pressed for time and can hold unconventional working hours. Try setting up a wiki, Facebook discussion group, blog, online chat, or e-mail listserve with students in a discussion section. As long as you can write clearly and do some moderate facilitating, this will allow students to field one another's questions and set you up with a pre-formatted method of sharing course material, posting announcements, offering tutoring/advice/support, and initiating discussion on course topics.
Because a teaching assistant is communicating with such a variety of individuals on any given day, good communication skills are essential to his/her success. Organization is going to be the key to good communication for any teaching assistant. The TA has to be able to interpret the teachers’ needs and wants as well as the students’ needs and wants and be able to cross communicate between both of them. Many times, the TA is the "middle man" between the student and the teacher. There will be times when students come to the TA with questions and he/she needs to be able to understand what the student is asking and answer the question, or be able to communicate the question to the teacher and then in turn go back to the student with the teacher's response. There may also be times that a parent or co-worker is looking for information that must be properly conveyed to a teacher and in turn conveyed back effectively. Both verbal and written communication skills will come into play in this position.
Personally, I rely heavily on my TA for weekly routines. We have developed an open communication line between the two of that enables us to almost communicate without speaking or writing. She has learned our classroom processes and is able to get materials together on her own without my instruction. We have set up a process that works effectively for both of us. Leaving short notes, in a “regular” place, has been a critical part of our communication process, as well as PLANNING.