-Learn to program. Take a few select CS classes if you can, but it's not required. Hell, I hated my CS class most of the time and dropped it towards the end of the semester. The professor kept pounding "Computer Science is not programming!" into our heads and he was right. I rather liked programming. I didn't like computer science. From what I've seen, read and heard it's a great skill to have. Familiarize yourself with computation and modeling programs.
-Read independently. Even if you're not presently knowledgeable enough to be of much use to a researcher, there's no reason you can't endeavor to understand their research and that of others. The more informed you become now the easier your job will be later. The required textbooks shouldn't be your only source of physics knowledge -- they exist to give you a general view and to help you pass tests. There are always better books to read if you're looking for something more specific, more up to date and more interesting.
I've happened upon a lot of great (and cheap!) finds on Thriftbooks, although you'll need to find other sources for more up-to-date research. Your campus library will likely have subscriptions to peer-reviewed journals and various online databases, ask a librarian to help you access them. You say you don't know what your focus will be.. this is a great way to help you figure that out.
-Not to sound all motherly, but with no job it'll be all too easy to lose focus. Set a schedule and stick to it. Exercise. Eat well. Sleep! Really. Sleep.
-As for research, well, I'm not far enough along to say anything authoritative except that I rarely see first and second years doing any sort of Physics research. Your best bet (until you're qualified) is to find an internship or join a faculty-supported student group. An internships can be thought of as research-lite; you may well find yourself researching or investigating something in the course of your duties but it won't involve original contributions to science. Nonetheless it can be a rewarding experience, both in terms of learning new skills and making potentially valuable connections in industry. Perhaps you could even wrangle an Independent Study credit out of it.
If that's not for you, there are always competitions and projects. Programming a robot, designing a vehicle, building a circuit, all things that are reasonably easy to teach a group of students. If you were further along in your studies the answer(s) would likely be different. Then again if you were further along in your studies I wouldn't feel qualified to answer!