How to earn an MD/PhD, the right program?

Currently I am a high school senior, though I wish to prepare early for my path on this medical-school journey. Right now, I am hoping to get admitted to a Biomedical Engineering major at a top 50 university because ultimately my goals are to pursue a medical research career in genetics (specifically cancer genetics). Besides undergraduate research, the MCAT, and grades, what are other things I can do to better my chances of admittance to an MD/PhD program? And what are some common paths people take to get there?

Oscar Hanson