My question involves paternity law for the State of: Colorado

I ma 29 years old and my biological father was never put on my birth certificate. He and my mother were never married. He is only occasionaly a part of my life. My step father is really the only true father I have ever known, even though I am an adult and so changing the birth certificate does really have a legal baring on anything, I just wanted to put my step fathers name on my birth certificate in a way to honor him. Can I do this and what do I need to do?