A few steps
Whole house
The paper
Colorado accepts a statement written at home. Fill in the blanks, print it, sign it.
Colorado schools and child care take the Certificate of Nonmedical Exemption, not this statement. This statement belongs in the home school record. A district asking for that record may see only the shot record or this statement.
The paper. Certificate of Nonmedical Exemption. The state publishes the form. It has to be written again every year.
This is a summary of public law, not legal advice. Requirements change, so always confirm with your state before you file.