Ill tell you how, but lets get past something first. All the ulzzang photos you probably seen and drooled over is definably Photoshopped. If you dont have photoshop or anything similar and you want to look like these girls, dont past GO. In this environment/community natural is but a fairy tale, you can have the best makeup but that is all that is going to take you. The makeup may be natural but that is not what makes you ulzzang.
Start to think "best face" means the best face you can make with makeup and photoshop.
learn how to put on makeup first and change your proportions.
Proportion, your eyes has to be the biggest part of your features, the mouth the smallest but the eyes are everything. So circle lens, big eye makeup. Try to avoid milk face where you are just pale, with no color, ashy and a void of white like the second one above.
Angles, angles , angles though this is just photoshop photoshop photoshop
Understand that photoshop is as kleneex to every brand of tissue.
Photoshop means editing your face now, not just the brand.
bright natural light., here is more milk face.
and more photoshop.
But if you dont want to be that extreme, do like me; I dont photo bend my legs, eyes, arms, head shape, or mouth, but I do approve of some hair it depends.
-I just smooth my skin out and give good eye makeup and highlighting so if you see me the proportions will always be right
-I will look validly the same in every photo because I dont have to keep up the false proportion
-editing will take less time so more pictures.
.....this is not puri, those legs are not proportioned.
and thats how you become an ulzzang.