This might seem like something fairly rhetorical (I hope), but stay current with your career field. What I mean by that is, update yourself on any new techniques, software, policies, technology, codes, etc. Career fields are always evolving and improving. Some change over the course of years while others over the course of a few months.
Once you graduate from college, you will most likely be very up to date, but as time goes by somethings are sure to change, in regards to your career field. Don't get stuck back in time. Update yourself every six months or so. Join circles that can help keep you updated on what's new in your field. Things like: online forums, career clubs and organizations, and websites dedicated to your field can be used to keep up with what's new.
This might seem like extra work, but once you get into the groove, it will become easier. Keep your skills relevant. It you are always evolving with your field, advancing won't be a problem in the future.