As part of the preliminary plan phase of the development approval process, the applicant shall provide the Commission with a pattern book that will address site planning, architectural, landscape architectural, and signage requirements for the proposed development. Once approved by the Commission, the pattern book shall govern development of the PEC - Planned Employment Center. If guidelines exist for the proposed development, such as the "Warfield Commercial Center: Design Guidelines and Standards for Signs and Energy Efficiency," then the applicant will follow them, or propose changes to account for changes in the land use, technology, or design approach. The pattern book shall be prepared by a licensed professional landscape architect, architect, or engineer.