If one of your languages is Japanese, it seems to me you could just J-Google it....
By "teacher", do you mean "public school teacher with a career" or do you mean "dancing bear who for a year or so after college pretends to teach English to people who pretend to learn English"?
If the former: You need Japanese citizenship and you have to pass a national licensing exam.
If the latter: You need a necktie and a pulse.
If I don't sound friendly, it's in part because we began our acquaintance with you having your androgynous buddy flip me off.