Advanced TEFL qualifications seem to be less in demand in France than business qualifications and experience or even just “commercial flair.” Anyone who has a BA and is comfortable in a business setting has a chance of finding teaching work, particularly if they have a working knowledge of French.
The Cultural Service of the French Embassy provides English Teaching Assistantship Program especially for the citizens of the United States. Postings are illegible for 6-9 months and are held in primary and secondary language schools or colleges for training teachers. Conversational classes can be given by assistants; they can also provide classroom support for US pupils who are not god in the studies. You will be required a major in French. So the better you know it, the more chances you will have to get a good job. The salary of assistants is about 900 gross euros per month.
Work permits must be obtained before leaving home, which is simply impracticable unless you have spent time in France and developed a working relationship with a cooperative employer. (Note that the long-established Paris training organization, WICE, at 20 boulevard du Montparnasse www.wice-paris.org, can advise on how to get working papers, though it warns of the difficulties.) Foreign residents who came with a student’s visa are illegible to work only 10-20 hours a week full time employment is possible during the vacations only. Most casually, board and room language exchanges are common in the capital - Paris; the agreements are made through the ads and in oral communication. You can do private teaching with students, going to their houses; you will probably get about 20 euros per lesson.
In Paris there are a lot of foreign communities from people who left their home countries long ago and live now in France. They can help assist you in useful advice on how and where to find a good job. One is situated in the lobby of CIDJ at 101 Quai Branly (Métro Bir-Hakeim) may be useful as students temporary jobs recourse, but sometimes you can find advertisements that are for a soutien scolaire en Anglais (English tutor). The earlier you come, the more positions you are to find (the hours are Monday-Friday 9:30 a.m. to 6 p.m. and Saturday mornings).