Early in your career you need to focus on your GPA and staying involved with clubs, and the community. Unlike some people in vet school a C does not equal DVM if you want specialize. Once again the pressure to make excellent grades comes into play. Also, find a specialist at your school that is in the area of your interest and let them know your future plans.
Any research opportunity you can come across and help with is a plus; ask the clinicans if they have any research work you can help with. find out if you can participate in the summer research experience. Most vet schools have funding from Merck to sponsor some small projects. I started working on research projects to help the residents and then finally in my junior year got the chance to head my own (Nutramax Labs really has a great intern program)which resulted in two absracts and one manuscript.
If you can attend conferences and network with some of the specialists. And once you get to do externships try to extern at speciality centers and other veterinary schools (helps to showcase your skills).
Other than that stay focused and dont throw all your eggs into one basket, a lot can change over the course of four years.
