He still gives presentations at KOTESOL (Korea Organisation of Teachers of English to Speakers of Other Languages) conferences. The one I went to was packed full of people wanted to see him speak. So it just goes to show you that being a TEFL teacher isn't an end-all job. You can easily use your skills to transition to another field.
Another great speaker is Liam Lusk who together with Carl Kwan have a website dedicated to teaching people about presentations. Their website, Pesentation Expressions has a neat post about the Top 10 Presentation Errors to Avoid. If you think about it, every time you give a class you're giving a presentation. So even if you don't teach presentation per se, this post should be able to help you out.
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