Start by looking at WMU's list of undergraduate majors. It might help to print a copy and cross off majors that are not possibilities. However, look up unfamiliar majors; they might turn out to be of interest.
Look up majors of interest on the WMU undergraduate catalog. In the catalog, choose "Programs" from the drop-down menu and then enter a keyword (name of major, vocation, etc.). An alphabetical list of search results will appear; scroll through to find the desired major.
Get more information on the relationship between a potential major and careers in the Occupational Outlook Handbook. Enter a major or career or interest and learn about the average salaries, working conditions, and related occupations associated with that field.
Take General Education classes in areas of interest (check with an advisor to make sure it is a good choice).
Meet with an academic advisor that specializes in the major of interest.