How would I go about making complicated clothing using sewing not sculpting?

I REALLY want something like Clo3d or Marvelous Designer but I don't have the money for it :P. So how might I go about making more complicated clothing (i.e. variants of dresses, layered clothing, ripped jeans, Infinity Nikki type stuff)? Because all I really can make at this moment is simple shirts, dresses, and pants. And I really want to move to the next level.