Private tuition is a tricky one to get into because it is hard to build up enough students to depend entirely on it, and private students can be unreliable. I think that some people who manage to break into niche markets can do this well; I know of someone who is successful among the Japanese community in London, which is a direction you might be able to follow as you have experience of Japan.
When you talk about prgressing, do you mean in career terms? If so, if you don't mind my asking, to what degree are you qualified, as there is a considerable difference, certainly in some countries, in the quality and conditions of work available once you've got a master's degree.
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