Someone who is not kadosh is viewed as the exception, not as the norm. All you have to do is act like God . The list of laws that follows is cumbersome, to say the least. It encompasses subjects from idol worship to sex to charity, and everything in between. The Torah seems to be saying that the blueprints for being kadosh are found in following the mitzvot.
Many people hold that view.
I think there may be another layer to it. The final paragraph of the V Ahavta prayer gives its own, somewhat similar, definition of holiness. To be holy is not merely to do my commandments, but rather to remember and do. The mitzvot are about more than actions. Being kadosh is more than a game of Simon Says.