What is the first step in derivatively classifying a new document is to refer to existing?

The first step in derivatively classifying a new document is to refer to existing classification guidance, such as previously classified documents or relevant classification guides. This helps ensure consistency and adherence to established policies and criteria. By analyzing the content and context of the new document in relation to these references, one can determine the appropriate classification level necessary to protect sensitive information. This process is crucial for maintaining information security and compliance with classification standards.