Wooden or asphalt?
Asphalt come in a variety of colors, I know you can paint over them but it never loks quite right.
Wooden shingles can be stained with regular household wood stain in a shallow pan or with tea dying as the person aobve me suggested. Wooden shingles can also be painted. I recommend if you paint to lay them out on cardboard or newspaper and spray paint them if you can. I did some by hand because the color I wanted was not available in spray and let me tell you, time consuming!!!
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