Random ideas. 1) As Francesco says, "know your audience." 2) Pretend that for some reason you need to transfer to another university and want to know about the campus. Write a list of specific questions of factual details you would want to know about the campus. How big is it? Is it in a city? If you don't have a car and want to go shopping, what are your options? Then write a description that answers the three most important questions. 3) In answering the questions, I suggest answering factual questions but using a personal point of view. Don't say "the campus is 4,000 feet long." Say "It takes me fifteen minutes to walk between two of my classes because my history class in Old Main and my English class in Wiggins Hall are at opposite ends of the campus." 4) It is very, very likely that Wikipedia has an article about your college or university and it might well include description of your campus. DON'T EVEN THINK ABOUT COPYING FROM WIKIPEDIA, it's the first thing a teacher will look for, but you can use it as a model that shows how somebody else approached the task, and you can pick out typical useful English phrases that might be helpful. Wikipedia is not brilliant creative writing, but it usually they good, accurate, correct English written in good expository style. For example: https://en.wikipedia.org/wiki/University_of_Iowa#Campus "The University of Iowa's main campus, located in Iowa City, was originally designed by architect D. Elwood Cook. The campus is roughly bordered by Park Road and U.S. Highway 6 to the north and Dubuque and Gilbert Streets to the east. The Iowa River flows through the campus, dividing it into west and east sides. Of architectural note is the Pentacrest at the center of The University of Iowa campus. The Pentacrest comprises five major campus buildings: Old Capitol, Schaeffer Hall, MacLean Hall, Macbride Hall, and Jessup Hall...."

It's very difficult to write a description. What's your purchase? Who's the readers of this text?

It depends on whether you like it or not :)