Career-Changer/Non-Trad Research Experience? How to Get?

I'm a career changer (about a decade out of undergrad) and am looking for advice on how to assemble my application. I'm planning on applying next cycle, but I have no research experience. I have clinical/volunteering hours, but I have no idea how to go about getting research hours as someone unaffiliated with a university. Any input? Is research even necessary?

I took the MCAT and scored well (520+), and my GPA was solid (3.9+) during undergrad.