Following fashion in South Korea

Personally I find it very easy to follow the fashion trend in Korea (as a foreigner) and that's because almost all shops have same clothes styles. Even if you want to wear clothes that you like or used in your country, it is very hard to find. Especially underwear or bigger size shoes for women.
Since I came to Korea I had to adapt my clothes but not to respect the "society fashion" but simply because I didn't have other choice ).
Fashion boutiques are everywhere in Korea so it is very easy to find them. There are also very big outlets where you can spend your money on expensive brands.
The price tag however it's very different. If you buy the clothes online (there are so many online clothes shops) , the price is cheaper than if you go to shopping mall (but I guess everywhere in the world is same).
Koreans tend to follow the trend and care about fashion very much. It will not be strange to go to some coffee shop and figure it out that all people are wearing the same clothes with same colors. They follow the blogs, or fashion advice's  a lot.
Women usually like to cover up but uncover down ) which means they wear long neck shirts but very short (almost invisible) pants or dresses.
For men the style is pretty simple : one pair of black pants or jeans and white shirt or t-shirt. Some of them are carrying  bags or bag packs, wearing caps and glasses.
From what I figure it out, hairstyle is part of fashion too and most of people tend to cut their hair and arrange it in the same way in order to follow the actual trend.