Clean the copper with soap and water
Degrease the surface with vinegar or alcohol
Rinse and dry completely
Lightly sand or scuff the surface if needed
Apply a patina solution with a brush, spray bottle, or cloth
Use ammonia fumes for a blue-green patina
Use vinegar and salt for a green patina
Use liver of sulfur for dark brown or black tones
Let the copper sit in a warm, humid environment
Reapply the solution until the desired color develops
Rinse the copper when the patina is complete
Neutralize the surface with baking soda and water
Dry thoroughly
Seal with wax, lacquer, or clear coat to preserve the finish