Very carefully!! Check under the car to make sure no cats or small children have decided to take a catnap under your vehicle. Look in back before you back up! Make sure there are no bikes or other cars. Tragic accidents have occurred when people don't pay enough attention.
Make sure the kids aren't fighting so you can see around the flailing arms and legs in the rearview mirror, get out and look around the suburban parked next to you, and then get in your Prius, and back out as fast as you can!