​Most people I met in Korea were absolutely wonderful and helpful, plus traveling around Seoul (which is the only place I actually managed in my small trip) is relatively simple. These are the only things I can think of for advice: ​

​

Metro: There is a METRO APP that you can download on your phone (Disclaimer: it doesn't work on a Chinese phone) 

• You can take pictures of the many METRO lines, but if you ever want to ask a local for directions... make sure you actually have a Korean version.​

Karaoke: Always a trap!  Also, you are not allowed to bring bottles of wine with you into the booths, so definitely play dumb if you get caught.

BBQ & other food: Delicious!!! But usually the best things you have to order 2 servings, so definitely go with a friend that has the same tastes or be prepared to feel super fat for your entire trip