Here is a must have map you need to get upon reaching myeong dong area. You can get the map from mobile customer service officers there or at the information counter at myeong dong.
The map will show you what are the shops available and where they are as there are many many many of the same retail brand names along every street there that will confuse your good sense of directions.
There would be about 3 to 4 outlets of Skin food, Face shop, Tony Mony, Missha, Its Skin, Etude House and even Dunkin Donuts etc each in just one myeong dong area. Or at least it felt like it.