Come see me tomorrow at the Kotesol Busan-Gyeongnam Symposium. It will be myself and 3 other speakers presenting on a wide variety of topics and promises to be informative and interesting.
Tip #7 from my presentation is smile! It's easy, but actually makes a big difference. I get so many comments from the students at the end of the semester that they loved my smile and thought that I was very friendly. Nobody likes a grumpy teacher unless they're some sort of freakish genius. But, chances are most of us aren't, so that leaves being friendly as the better option.