I've been hiring in Thailand for a long time, and here's the teacher that I'm looking for in a nutshell...
Someone who looks presentable and will show up each day on time. I've turned down better qualified people in favor of someone who I thought would be more likely to stay in the job for a while. I've taken chances on people based on my gut feelings on their potential to grind it out and do the job without kicking up a fuss. It's not a foolproof system.
So, what hints are there that you're the right person for the job? What can you do to persuade an employer to take a chance on you?
Well, if you live nearby and you have a serious girlfriend or wife (and if you have kids that's even better) then bring her to the interview with you. You have a car? Then mention it. Most teachers don't.
Although I would prefer to hire more female teachers, I tend to avoid them. In my twenty years in Thailand it's my opinion that while females make for better teachers, they don't stick around for long and hop from job to job or get pissed off and run back home.
I prefer British people over Americans. Americans don't stay in Thailand all that long and they complain more than Brits. Brits aren't so risk averse and can tolerate changes in a foreign culture better than our friends across the pond. Americans have higher expectations so the fall for them hurts more.
More experienced teachers are harder to work with. They don't easily accept their reduced importance in the grand scheme of things and too many of them have personality problems that aren't easy for them to cover up.
Younger teachers are pretty good bets, except of course that they aren't really here to 'teach'. This sojourn to Asia is part of their great world adventure and they're often too focused on themselves to care about what I want from them.
Certain non-native English speakers are just aggro all the way. They don't listen to good advice and have this unwarranted arrogance and overblown faith in their 'abilities'. Their teaching priorities aren't the same as mine and they refuse to be re-trained to do what I want them to do.
Finally, teachers who take up the cause just to fill in their days are a bust, too. I like to have a little leverage over the teachers that I hire. Therefore, if you've already got a fat pension or a big wad of dosh in the bank, then I will probably look past you in favour of the guy who 'needs' the job.
So.... if you're an Englishman with a degree, around 30 years old, can work a tie knot, and you are already settled near where you want to work, and you don't have another income or much in the way of savings (and you like run-on sentences) you've got the job! Congratulations!