Decide on the type of graduate program that interests you. Much of this information can be found in the Peterson’s Guide.
Explore graduate programs and evaluate how well they meet the criteria important to you. Keep in mind that there are differences between general catalogs and departmental catalogs. Departments will give you more information about faculty and coursework; you usually have to request these form the department you’re considering.
Talk to faculty members from the program to help you learn about graduate school rankings and answer other specific questions you might have.
Narrow down your options. Talk to the graduate advisor in the department you are considering or set up a campus visit. Ask for the names of current graduate students who can talk to you about their experiences.