While doing fun stuff is an important component to your med school app, relevant stuff is equally important. You’re going to need experience, paid or unpaid, in the field of medicine. This can be done either, or better both, through research and clinical exposure. Every strong applicant needs to have research and clinical experience to make their application competitive.
Spending time in a lab, that is neither required nor credit awarding, is always a great decision and there are many ways to accomplish this. Working with a professor on one of his/her projects, whether you’re splicing DNA or cleaning test tubes, provides you with more experience (bonus: potentially a great letter of recommendation). I spoke with the head of the biology department at my university to let him know my desire to become involved in any of the projects going on in the various research labs. My name was sent via email to graduate students working on their own projects who were more than happy to have an extra set of hands out in the field working with the animals. And again this shows your fascination with science understanding of work ethic, etc. Just do it (is that plagiarism?) and you will undoubtedly benefit.
Clinical experience can be slightly more complicated to accomplish in this country without having any sort of certification or letters listed after your name. Much of this involvement requires volunteering. If you are an athlete, a double major, a socialite, if for whatever reason you are unable to make regular additions to your academic schedule, it is simple to gain experience during any one of your 8 winter and summer vacations. Shadowing a physician for 2-3 weeks is a quick and easy way to interact with patients. Finding a physician who will allow you to shadow them can be accomplished by asking family friends, your own doctor, your pre-med advisor, or finding a list of local physicians who are alumni at your school and emailing them. I shadowed a family friend at a local hospital during winter break and came away with operating room experience, a passion for cardiology, a letter of recommendation, and a lifelong mentor.