Cats may step on people for various reasons. Some cats may step on people because they feel dissatisfied or want to express some emotion. For example, if your cat feels neglected, it may stomp on you to get your attention. Some cats may also step on people for play purposes, just as they would step on their own toys. Other cats may step on people because they feel they need to protect themselves or their family.
If your cat often steps on people, you may consider providing it with more opportunities to play to help it vent its energy. You can also try providing your cat with safer play objects, such as scratching posts or cat toys, to help him meet his play needs. Of course, if your cat's stomping behavior seriously affects your life, you may need to seek professional help.