I think this would vary significantly based on what field you're planning on going into. For some fields, your degree doesn't matter. For others, it really, really does.
In my case, my degree didn't matter much at all, but several of my unpaid internships were absolutely crucial. I wouldn't have my current job if it weren't for my unpaid internships. (It helped that my alma mater has some good name recognition, but I know for a fact that I would have gotten this job even if I'd graduated from an unknown school.)
Edit: I recognize that not everyone has the luxury of being able to afford doing an unpaid internship. In those cases, I would still prioritize summer/semesterly jobs relevant to whatever field you're going into. Even work study jobs doing data entry for the admissions office will count as office experience later on. As long as you graduate with something marketable on your resume, your major shouldn't matter much.