explain shell theorem to me like I'm a retard

if I want to populate both the inside and the outside of a dyson sphere with people and I want them to experience the same gravity, how should I rotate the sphere? specifically, if the sphere is made up of an inner sphere on which the inner man stands and an outer sphere on which the outer man stands, should the inner sphere rotate faster? should the outer sphere rotate at all? how would the mass of the sphere itself affect the difference?