Should I reply in bold type? 😉
If you have some extra time for reading, read things that you enjoy! I had so little time to read while I was in undergrad. I really missed being able to pick up a novel just for fun. Science fiction, fantasy, non-fiction . . . fun reading is so great. Enjoy it while you can.
I'm not sure how much of a 'head start' this would give you, but you could always look up case studies and research papers to read. Hang out on sites like Science Daily for news and more easily accessible info, or explore google scholar and find things you're interested in. If you're looking up papers, I'd say read for the basic ideas and don't get hung up on learning everything about the science and protocols, especially if you don't have a science background yet.