1. Get a T-money card
This is the first thing you should do when you arrive in Korea. I got myself a T-money card at the convenience store at the airport, it's something like a touch-n-go in Malaysia, but a more 'versatile' one. It costs 4000 won if not mistaken. You could use it to pay not just for buses and trains, but also your taxi fare. You can also use it to buy stuff at certain shops or convenience stores.
2. Never buy cosmetics in Myeongdong
Myeongdong is known for its streets with super many cosmetics stores but almost all the cosmetic branches do not have much sales or promotions. I presumed it's because they don't need promotion to attract tourists because the place itself is touristic enough lol. I bought most of my cosmetics at the cosmetic branches at some random streets in Ewha or Samcheongdong (I couldn't really remember) before I visit Myeongdong. Initially, I was a bit reluctant to buy because I thought Myeongdong will
