If you were to retopo something fabric to incorporate these folds and wrinkles, how would you go about doing it?

During this tutorial, Jonathan retopos the head/hands/face, but skips the clothes like this jacket, since they are still somewhat animation friendly. However, for a game asset, for example, how would you go about setting up your face and edge loops around the folds? Or, would you just have to overpower with tons of geometry?

Thanks!

Ryan