Myalgic encephalomyelitis, also known as chronic fatigue syndrome, is a very challenging multibody disease that historically suffers from a lack of knowledge about physical therapy and its practice. The similarity between this disease and Long Covid makes general advice, evidence for physiotherapists, more timely and important. This guide includes a detailed explanation and medical history of ME/CFS, including symptoms, differences in severity, and how to manage ME/CFS in children. Additionally, patient case studies provide detailed management information and discussions of how data can be directly linked to physical activity.