Each school or college has general rules for what documents you must prepare. But besides your papers, each college has  list of specific requirements for each student. I know that many colleges want to read an admission essay in which you write about your motivation, what your personal and school achievements are, and why you want to study in the specialty you have chosen. I can say that it's very difficult to choose the right strategy for writing such essay, because you don't know how members of the selection committee can understand your text in different ways and this essay influences the approval of your application no less than good GPAs. I can advise you to read the best admission essays online on this topic and understand how best to write it, that it will make good impression about you.