Get to know your professors, and develop a relationship with them so that you are comfortable enough to approach them when you need help or need questions answered. Always try to make an effort to solve a problem on your own first. If you are still struggling, take advantage of their knowledge and willingness to help.
Start building your network as early as you can. Your network can be your professors, your peers, or people you've met at extracurricular lectures, networking events, workshops, or internships.
One limitation of education is that a lot of time is spent learning theory, but very little time is spent getting experience on how things really work in the outside world. An excellent way to get experience and meet people is to seek out summer internship opportunities early on, and use your internships to build a portfolio of products/projects. Prospective employers will always view a graduate more seriously if they have had previous work experience.
Along with experience, make sure your science and math skills are well developed, as well as your writing and presentation skills. You will need to work well with teams, both at school and when employed, so patience and listening skills that are developed early on will come in handy. Having said that, you still need to be assertive, be able to get your point across in a respectable way, and be able to work on problem solving with others.