how do I fix this ?

If you can't tell from the picture it's on the rear bumper just above and to the right of the licence plate.
I was thinking of just getting some touchup paint? not sure if I should repaint the whole bumper I'm worried the paint might not match, then again this looks bad. What would you guys suggest ?
I don't know how this happened, what hit it, etc. It's wierd. When I pulled out of my garage it was not there, went directly over to a friends where the car was parked outside on the street for 5 miuntes. I was outside near the car the entire time. We headed for the track and when we stopped about halfway there I noticed it. Only thing I could think of is something fell off another vehicle on the highway ? Still the angle it would have had to travel seems almost impossible. Maybe someone thew something out a car window ? I don't know.
My car is in excellent condition and I hate when stupid stuff like this happens
How would I go about preping that for touch-up paint?


