Research the course carefully. There are many TEFL courses available, but often the cheaper option will lead to a less respected qualification. Ensure that the course has these criteria: 100 contact hours with a tutor; at least six hours of assessed teaching practice; and coursework amounting to 3,000 to 4,000 words.
Become familiar with the destination country if studying an international TEFL course. Knowledge of cultural norms, key phrases in the language and how to get around can all help to make the transition smoother. Most important, ensure that it is possible to obtain all the necessary visas to be able to study and work.
Review English grammar. A grammar tutorial may well be part of the course, but grammar is the most technical area of the job. Useful texts include “English Grammar in Use” by Raymond Murphy and “The Good Grammar Book” by Raymond Swann and Catherine Walter. The most important aspect to be familiar with is English tenses, how they are formed, what they are called and why they are used.
Research the types of classroom technology and resources available to a teacher in the destination country. Previous teaching experience might not be relevant or helpful to teaching TEFL. It is a very specific skill that is quite different from most other forms of teaching.
Practice judging other people's teaching methods. The TEFL course usually demands that students critique the lessons of their colleagues. New students should contact TEFL graduates before the course begins to make sure the atmosphere will be a friendly one when it's time to deliver criticisms and work on group assignments.