This was another quick and inexpensive customization of a discounted, scuffed frame.
This plastic/composite frame had a couple of white scuffs. I wanted to use it with an antique photo, so the frame should appear worn and scraped up. I took a piece of sandpaper and lightly rubbed some vertical scratches on all sides. I wiped, rinsed, and dried the frame to remove any dust. Then I took a small amount of black craft paint and a paper towel and rubbed paint into the scratches, wiping off excess paint to leave green as the main color. I let the paint dry and reapplied until I achieved the look I wanted.
I really like how this turned out - giving a modern-colored frame an antique feel, but still maintaining the vibrant color. It works very well with the colors in this reprinted photo of my grandfather, taken in the 1920's.
Were I to do it again, I might use a finer-grain sandpaper and perhaps experiment with different scuff angles, or even used a knife to dig in some deep scratches. I could use multiple paint colors to give the scratches a variety of shading.