Small dents on rear bumper

[Arthur]

Hi, I have two small dents on my rear bumper as a result of another car lightly bumping me while I was parked. The bumper is not cracked, it's just scratched. I have smoothed the dents with fine sanding paper.

My question is (please keep in mind I'm a total noob): should I buy one of those touch paints in the small bottle or would it be easier buying spray paint or with a brush perhaps?

What's the best way to handle this? Thanks in advance.