Everytime this thread pops up, every year everyone says the same thing...
But I'm gonna go against the grain a bit and say If you think you might want to GUN your way into a competitive specialty AND If your school is ridiculous enough to employ a grading system the first year AND ESPECIALLY IF you were a NON SCIENCE MAJOR... forget what everyone else is saying -- AND START STUDYING NOW!!!!!

Buy yourself a BRS and netter start memorizing those origin/insertion innervation and blood supply musculoskeletal tables TODAY!!! (Or get the appropriate BRS for whatever your fall classes happen to be and start lookin at it!)
Why?
If your school is one of those schools mentioned, you will find yourself at an unfortunate disadvantage and in the unfortunate circumstance of being graded against individuals who have already taken that basic science course already. Which sucks, cuz the grading distribution in the beginning seems to reflect prior course knowledge moreso than anything else... Haha well at least until the non science majors start to realize they actually have to put in 10x the time in learning something relative to their peers and begin disappearing from the social radar to catch up!!!
If the aforementioned doesn't apply to you, then like Clockworkdoc says, Get laid and relax
👍