Tips For Making Korea Work For You
It is not the knowing that is difficult but the doing.
               -Chinese Proverb
Whats The Best Advice You Could Think Of Giving Someone Coming To Korea? "Don't!" many would say! But if you're looking for a challenge and perhaps an adventure you might consider the following:

i) Keep the big picture in mind and try not to focus on all the little inconveniences that inevitably occur and that may include things like substandard housing, small scale lies and cheating (if serious you should try and change jobs), weak curriculum, babysitting operations, xenophobia etc. If you get into a major tiz every time somebody rips you off a bit on your overtime pay, or on your taxi fare, or because they lied to you about your apartment etc then you're probably have a rough time here. In the west we tend to have quite high standards regards lying and cheating and so. But this isn't a first world country over here. If you try and apply those western expectations you're often going to be disappointed. Think third world rather than first and you won't be disappointed. Its not really eg Thailand but its closer to Thailand than say Japan or what you're used to at home. You need to step back and eg if you've been cheated out of 200000 of overtime or whatever look at what you're making for the whole year, 20 mill or so and just put it down to the costs of doing business in Korea. Other costs like taxes at only 7% are very low here. So leave western moral expectations at home, keep things in perspective and you'll be much happier.

ii) Make an effort to learn about maximizing your teaching skills. Yes teachers do sometimes get fired, sometimes with just a days notice. Sit in on other teachers classes to pick up tips, copy copy copy, have a look at the fun educational games on Daves Cafe
http://www.eslcafe.com/ideas/index.html etc. Basicaly the better teacher you become the better things will go at work which is where people in Korea get stressed out. After all you don't hear of tourists here getting stressed! Another thing is that people think that they're on a wage here or that they can have a working holiday here. Not! You're certainly be working but a holiday it sure ain't. Remember you're be stuck in one place with only a few days off in the year to explore the country. As for the wages you're not on an hourly wage! You're on a salary the same as if you would be as a teacher or professional back home. The difference between a salary and a wage is that you are paid for doing a job rather than by the hour. A lot of people get confused over this. Even through your contract may state just 30 hours of teaching thats not the end of your job. You are expected to do all the preparation, test marking and report writing etc that gos with doing the job. You won't be paid for these extra hours cause you're not paid hourly. Its the same as if you were teaching back home. You may have classes from 9-3 or whatever back home as a teacher but outside that you have to do all the other work. A lot of people here in Korea (including myself initially) try to skimp on this other work, esp on prep, but this won't give a great impression to your boss. Also if you do become a really good teacher, and they can see that you are, you can command much higher salaries like 2-2.5 instead of the usual 1.6-1.9.

iii) Choice of hagwon. If this is your first tour of duty I would suggest starting with one of the chain schools like ECC that are well organized and have a strong curriculum. A smaller mom and pop operation may not be able to give you the support you need. If you're not from the States or Canada and you have a strong accent try to avoid teaching adults since they will complain and complain and mostly behind your back to your boss. Needless to say this won't make you look good (no matter how great you might be with the kids) so forget about getting those higher salaries and you may be lucky to hold your job. This will also enable you to avoid those early morning classes (starting at like 7:00 am) that teaching adults entails. In fact even for those without accents try to avoid split shifts, Saturday work, and lots of compulsory overtime, if you can. Most hagwan jobs have at least one of these though, but its possible to obtain one without any of these (I have).

iv) Talk to at least two (theres always one with a brown nose) and preferably all the teachers by phone (they can easily fake emails) before signing anything. And/or post a query on Daves Cafe and check the graylists. This is vital! A lot of teachers still don't even email and hence some people still get into messy situations. Ask them lots of questions including things like how many teachers have left before completing their contracts, do they pay in full and on time etc. Refer to question 7 for other questions worth asking.
   Also note that the teachers there may have some contraints on how honest they are able to be when they are talking about the school (esp if its by email since may comes back to bite them). If they're waiting for their kast pay check, severence money and airfare (say $3500 all up) they may not be able to be totally honest! This particularly applies if theres only one other foreign teacher since they know exactly who is putting the bad word out. Also schools can be reluctant to supply more  then the usual one brown nosers email because even at OK schools the teachers are often depressed/stressed/homesick and have at least a couple of complaints. You may find if you insist on speaking to at least a couple of the teachers they may pass you over since they may assume you will be put off even if you just want to know if the teachers there are paid in full and on time. If you come up against this problem you may have to rely more on posting a general query on Daves Cafe and the graylists. 

v) Learn Korean. The more you learn the better things will go with your boss and your students. Most teachers in Korea don't really pick up much (unlike say Japan) but the best teachers (read: best paid) I've seen all learned and used a good bit.

vi) Understand a little of the Korean mentality. Those who come over here can be a bit puzzled at first. Theres this contrast between those Koreans who are very friendly and those who can be distinctly frosty. Theres this real ambivalence in their attitutes to foreigners. What explains this? Well on the one hand Westerners (and esp Americans) are seen as being very rich and powerful. Its also where Hollywood is which has a hugh influence. In this respect you will be highly regarded. You may think their response to foreigners can be somewhat exaggerated compared to other countries like Taiwan or Japan. Many people become addicted to this "being a star". On the other hand theirs another response which you will soon come up against. Because paradoxically part of this friendly response seems to come from Koreans having feelings of inferiority about themselves and hence and exaggerated opinion of others. And yet they also think very highly of themselves. It wasn't long ago that they used to call foreigners barbarians. This is where you can get into trouble for you have to be very aware of not offending heightened Korean sensibilities. They can be very touchy to say the least. You only have to look at Daves Cafe to see how things can go wrong. The opinions expressed on Daves tend to be on the extreme end. However a casual glance seems to confirm that a lot of teachers (if not a majority) seem to be a bit depressed which is in marked contrast to teachers in Japan and Taiwan who are mostly a happy lot. Here we are attempting to turn the tables on that. So with regards to Korean sensibilities, If they don't feel you are showing the "proper respect" they can turn very quickly.
   How to approach this situation? Well by being sensitive you can smooth over these problem areas. I tend to be extra polite, friendly and flatter shamelessly to a degree that would be regarded as strange back home or in say Taiwan. They have a formal social structure in Korea so lots of politeness goes down very well and is considered to show respect. Extra friendlyness will help melt these feelings of ambivalence. Flattery helps their ego which is a little battered but fiercely proud. Of course a little Korean helps immensly and they really feel it shows respect not to mention making it easier to get around. The Japanese and even the Chinese have had a similar tendency to the Koreans to litteraly shut out foreigners from their country. The only reason this has changed at all is because of the ascendency of the West although this they tend to regard as a temporary phenomena. They could be right. The Romans similary swept away the Greeks despite the Greeks cultural and scientific superiority. So be polite, friendly and remember a little flattery goes a long way.

vii) Getting on with your boss and co-workers. A large part being happy in Korea is being happy at work. And an important part of being happy at work means getting along with you boss and co-workers.
   Keeping your boss happy largely just means doing a competant job which we've looked at above. If you are teaching the kids something in an interesting way, and they like you, you're most of the way there. Otherwise just all the usual things hold for keeping your boss happy as in the west. If you know how to do that you should have no worries. One thing with Korea though is the hierachial nature of their society. So remember to always be respectful (or at least try!) but at the same time be assertive when you need to. Also call your boss "Won Jung Nim" (director/boss). Never Mr So and So. In Korea Mr is reserved for lower positions.
   As regards your co-workers lets look at the Korean ones (hopefully you can get along with your foreign co-workers). Actually the vast majority of your Korean co-workers will be female and under 30yo. Now there are a couple of things that you will have to do here to save yourself some trouble. Firstly for the first month or so you are expected to give them small gifts like candy, fruit and drinks. The women will also give you small gifts. The second thing is that you must make an effort to make conversation or at least small talk with them. They may sometimes be too shy to say much to you but you should with them. If theres not much conversation going on they will blame you and think you don't like them. Of course it may be nothing of the sort but thats beside the point. Now if you don't make an effort and you take a live and let live attitude they will as noted for some reason think you don't like them. I've made this mistake myself. They will then quite shamelessly do things like complain about things you do (eg in class) to the director and then tell you what they have done. "Why didn't you come and raise it with me first?" you will ask and ask over and over again. You will then end up thinking, like many foreign teachers here, that of most Korean teachers a few are angels but most of them are complete b***hes. Yes well the odd one may well be but the usu problem is that many teachers fail to follow the above two practices  regarding gifts and communication. Belive me those two little things (and point vi)  make a hugh difference.

vii) Other tidbits: One very important thing with Koreans is punctuality. Even if you're literally just two minutes late your director will likely take it very seriously and will probably have a talk with you. I've even had privates harp on about and make sure I knew there was no excuse for it if I was four minutes late. So now I always aim to get somewhere five minutes before the prearranged time. This they seem to regard as being on time. Different conventions. Where I'm from being up to five minutes late is considered being on time.