How to make yourself more marketable:
Maintain a 3.0 or better overall GPA:
Of all the acronyms that could potentially effect your job/graduate school prospects, your GPA will almost certainly have the greatest impact. Simply said, the higher your GPA the more options you will have. The standard cut off for many employers/graduate schools is a 3.0. The more competitive (in demand) a job/graduate school program opening is, the higher the GPA required to attain it.
Add a secondary major or minor:
Almost every major/minor offered on campus can "work with" the economics major. You can use your secondary major as a way to enhance or showcase the skills you will need for a particular job or graduate school program. The major/minor you choose to add to your economics major will of course depend on what your goals are after you graduate. If you want to got law school, you might want to add a major in philosophy. If you want to be an actuary, it makes sense to add a minor in actuarial sciences. If you want to work outside of the United States, adding a foreign language major or minor would probably be a good idea. If you want to study economics in graduate school, it might be wise to add a statistics or math major/ minor.
You can also use a second major to expand the realm of job/graduate school opportunities that you will have after you graduate from VT. Do you think you might want to work with computers? A minor in computer science might be a good choice. Do you think you might want to be a journalist? A secondary major in communications or English would make sense. Do you think you might want to be a history professor? Adding a history major would keep your options open.
The College of Science route in economics is far more conducive to adding a minor or secondary major because of the number of free electives in that program. If you go the College of Science route, you can often finish the requirements for two majors in four years (assuming your secondary major isn't in architecture or a major in the College of Business).
Get Involved:
Student leadership opportunities abound at VT. You can be a Hokie Ambassador (they give campus tours). You can be an Orientation Leader (they help out during new student orientation). You can be a staff writer, advertising director, web designer, or editor for the Collegiate Times. You can help invest some of VT's money by becoming a member of SEED or BASIS. You can get involved with the Undergraduate Honor System or the SGA. Participating in on campus clubs and organizations is a terrific way to develop leadership skills, gain insight into a career field that you are interested in, build your resume and/or develop relationships with people who might later serve as a reference.
Get a job (or an internship):
One of the best ways to increase your employability is to be employed. Your job or internship doesn't have to be directly related to what you want to do after you graduate, but it would be nice if it did. Either way, a job or internship will provide you with additional resume material and your supervisors will be good potential references. Of course a good internship might also serve as a way to "get your foot in the door" at a company or organization you would like to eventually to begin your career with.