1. Know your roles & duties as a TA

Clarify with your course instructor about your expected roles and duties.
Some common ones are:

• leading tutorials 
• conducting laboratory sessions 
• marking papers, book report, lab reports, quizzes, tests, exam,essays, etc. 

Reminder: 

TAs of different schools/departments may have different responsibilities. 

2. Meet your course instructor in advance before the semester begins

Take the initiative to contact your course instructor through email, memo note or phone call and arrange a meeting. (Check the University Communication Directory as needed) During the meeting, you can:

• Introduce yourself, including your academic background and teaching experience, if any, since your instructor may not be aware that you are a new TA who may be unfamiliar with the UST environment; 
• Discuss what you are expected to do as a Teaching Assistant and explore what knowledge and skills are needed to perform these duties. Let the instructor know that you may not have enough knowledge and skills to perform certain assigned duties so that he can arrange training opportunities for you and/or coach you at the start; 
• Consult the instructor if he/she has a plan/schedule for tutorial/lab sessions and ways that the sessions are conducted or you have to plan all the sessions by yourself (or with other TAs working at the same course). You may ask for past activities in these sessions so that you can have a better idea of what to do; 
• Ask for all teaching materials, such as text book, course outline, reference articles, lab instruction manual, etc. so that you can prepare ahead of time; 
• If you have to mark assignments or quizzes, ask if there is marking scheme or you have to create yours. Also ask for expected turn-around time since students are always earnest to know their
  marks and your instructor might have promised them when the marked assignments are returned; 
  Set your office hours, if needed and agree on mode of communication with your instructor, e.g. call your pager, email you or leave you notes in the department office, etc.; 
• Ask if you are expected to attend lectures with students; 
• Ask for resources in the department/school that you can make use of in your work, e.g. reimbursement of xerox cost, use of transparencies, assistance in printing, purchasing procedures, etc. 
• Find out how would your performance be monitored and evaluated*, e.g. how often you are going to report to the instructor and in what ways; is there any course-end evaluation of TA’s performance; what are some rules and regulations of the department/school in relation to
  TA’s work, etc. 

* Most departments have standard instruments to evaluate the TA’s performance. Ask for a copy of the instrument (questionnaire) and discuss with your instructor to see if both of you can agree on the criteria for evaluation, i.e. what constitutes "good" or "excellent" performance since different people have different interpretations of being "good" or "excellent" in a work context.

3. Meet your course instructor regularly throughout the semester

For several purposes:

• to keep the instructor, your supervisor, posted of your work progress; 
• to coordinate that consistent information are given by your instructor and yourself at different occasions; 
• to manage your work and study more effectively with good coordination; 
• to channel students’ feedback for course improvement; 
• to discuss ways to improve your work and students’ learning; 
• to solicit resources to facilitate your work. 

Most instructors would like to meet you personally to talk about your job. In cases that face-to-face meeting is not feasible, draft a brief work report in memo, send an email, or simply call him/her on the phone. Again, you have to take the initiative to do so!

4. Keep a record of your work

This practice would be of particular value to those TAs who would keep on their TA work or plan to embark on a teaching career in future. Documentation of what you have done helps you to reflect on the effectiveness of your work and provide evidence during the evaluation.

출처;http://celt.ust.hk/ta/tahome05_2a.htm