Most Helpful Guy
Play music that is popular for the age group you're marketing to, or if it's for all age groups. Make sure the angle of the camera is not uneven so that things don't appear 2-dimensional, and um... When you advertise, appeal to people's emotions, appeal to people's fantasies, appeal to their ignorance and superstitions. Tell girls that they will be respected, that they will be loved, that the best jobs will come about and that guys will be staring. Something like that, but more eloquently put.
Most Helpful Girl
It's Not about age but if you're truly passionate about helping others and sharing knowledge. That's a god given gift.