Punk hit my car. How to touch-up paint?

While in the gym, someone hit my white bumper, leaving chipped paint, exposing the black metal underneath the paint. Getting the paint repaired will cost me $600. Being a college kid, I don't have the funds. Is there a cheaper alternative to paint my car white again?

Added (1). Edit: It is a 2014 Ford Mustang.

Depends on whether you want it to look right or not. You can attempt touchup paint or a spray, but I can guarantee you that it won't look good. Getting it fixed professionally is the only way to make it look good as new.

Go to the dealership, give them the VIN, and they will be able to match the paint exactly. A small container of touch-up paint (comes in a tube with a built-in brush in the cap) will cost about $10-15. Will it look perfect? No. But like you said, you don't have the money.