/3/ - 3DCG

I'm trying to make a full 3d model of Gwynevere from Dark Souls, a.k.a the giant boob lady.
Fun fact, even Fromsoft themselves don't have a model of her, they half-assed it and it's literally a half-empty shell with a slap-dash rig.
I want to ask how do I make those creases on her bra?
I've been doing models of things like mechs, and guns until now, so cloth physics, sculpting are new to me.
So my questions are:
1)Should I subdivide the model and try and sculpt in the creases with the brush?
2)Should I instead texture pain them and apply to the normal map?
3)Since I'm an amateur,and never done production assets, I've never once done "baking"? Can someone link me to a tutorial or some general best practices?