Teaching English as a Foreign Lanauge (TEFL) is a course tailored to those whom wish to enter the vocation of teaching ESL (English as a Second Language).
Most recruiters will expect applicants to have some sort of TEFL training, and at least a 120-hour, four-week course. It should be conducted by qualified trainers and include at least 6 practicums, preferably with real ESL students.
Those entering the TEFL world should take the trouble to research the various courses and certifications. In recent years a lot of online TEFL courses have become available, but prospective teachers should be wary of these, since they are not always accepted. Without some experience and face-time with students, and the general classroom environment, the training falls short and you are unlikely to succeed in teaching interviews.
Who can teach?
Anyone with a fluent use of English language and the confidence to manage a classroom can teach English. You do not need to be a native English speaker or a certain age, although those between the ages of 21 and 45 are favored. The patience to work with kids (mostly) and ability to work at the blackboard with good presentation skills are also important.
To teach TEFL in Thailand you will need to have a general degree in order to get a temporary license (valid for up to four years), most recruiters also expect to see a 120-hour TEFL course. If you plan to make a career out of teaching English then you should consider studying towards a full, one-year teaching diploma, such as the PGCEi (Postgraduate Certificate in Education International) or similar, with which you can land better paid jobs in international schools. Such is the demand for teachers; some recruiters will have lower expectations although their jobs are less desirable.
Once you have completed your training, it doesn’t take too long to adapt to the routine of the classroom, within six months you will certainly have the confidence required to manage a classroom on your own. But most TEFL teachers are actually auxiliary language specialists floating among classes that already have their own local Thai English teacher.