“You watch the hood, I’ll watch the skies” is a phrase with roots in military and police culture. It’s a way of dividing up tasks and responsibilities, with the person watching the hood (the ground) being responsible for close-range threats, while the person watching the skies is responsible for long-range threats.
This phrase can be applied to a variety of situations, both military and civilian. For example, in a military context, it could be used to describe the division of labor between ground troops and air support. In a civilian context, it could be used to describe the division of labor between a driver and a lookout, or between a security guard and a surveillance camera.