It all depends on the shoes. What shoes are you having trouble with? They usually explain what you need to do to conform the shoes properly in the README file. Some (such as PhilC's V3 boots) use morphs that are included with the shoes. Others, such as those in the DAZ V3 HiHeel pack use poses which bend the feet and toes. For the latter, it is best to lock the feet and toes after applying the pose.