hello, legal requirements to work in Thailand are a degree in any subject and to be a native speaker.  Pretty straightforward really.  A TEFL is desirable but not essential (I'd definitely suggest doing one though) and.........that's pretty much it.  Shame your only 18 and don't have the degree but I sispect a lot of countries will have this as a stipulation.  Maybe not EU countries because you don't need visas.  You thinking anywhere specific to go or you just researching everywhere?  Any more questions about Thailand feel free to ask :-)

Gareth

Hey,

Welcome to Chalkboard. Great to see you're interested in teaching abroad.

To get you started on the site you may want to take a look at the groups to get an idea of what teaching in different countries is like:

http://www.onlinetefl.com/tefl-chalkboard/groups

Also you may want to have a chat to these members who are currently teaching abroad - they will be able to give you lots of help and advice about teaching abroad:

China: http://www.tefl-chalkboard.com/rozel09
Japan: http://www.tefl-chalkboard.com/pdixon/
South Korea: http://www.tefl-chalkboard.com/duggand and http://www.tefl-chalkboard.com/lintse07
Thailand: http://www.tefl-chalkboard.com/garethopenshaw

Enjoy the site and feel free to ask me any questions you have :-)