Preheat your oven to 350 degrees.
Line a cookie sheet with aluminum foil for easy cleanup.
Put one cup of bird seed into a medium-sized bowl. Add food coloring a few drops at a time. You can use one color or a combination of many colors to achieve your desired shade. Stir with a plastic disposable spoon to evenly distribute the color on all of the seeds. Add more coloring if a darker color is desired.
Spread the colored seeds in a single layer on the foil-lined cookie sheet. Place the cookie sheet in the preheated oven for 2 to 3 minutes. Allow the seeds to cool. They are now ready for use and safe for the birds.