The Facility Cybersecurity Capability Maturity Model (F-C2M2) assessment was designed to help facilities address their unique cybersecurity challenges. Building upon the foundational principles of the U.S. Department of Energy (DOE) Cybersecurity Capability Maturity Model (C2M2), the F-C2M2 was explicitly tailored for federal facilities to help evaluate, benchmark, and enhance the cybersecurity capabilities of both their information technology (IT) and operational technology (OT) environments. This user guide was developed to facilitate a thorough understanding of the tool. Whether users are familiar with the original C2M2 or are new to the maturity model concept, this guide was designed to offer clarity, direction, and support.