Sterilization of reusable tools involves using high-level disinfectants or autoclaves to sterilize any tools that are not disposable, such as metal tweezers, scissors, and extraction tools. This process eliminates all microorganisms, including bacteria, viruses, and spores, ensuring that tools are safe for use on the next client. Sterilization is critical for preventing cross-contamination and ensuring the highest standards of hygiene and safety in the spa.