The guide is primarily aimed at individuals suffering from severe obesity. It provides fundamental information about obesity as well as common physical and psychological accompanying issues in adults. Furthermore, the guide describes the factors that can contribute to the development of overweight and obesity and presents treatment options. In particular, it focuses on multimodal therapy, which guides a structured dietary change and increases physical activity, and has proven effective in studies. Initial steps for independently managing obesity are illustrated with numerous examples. Additionally, motivational aspects are addressed, and exercises are provided to demonstrate how to achieve a realistic target weight and behavioral goals for changing habits.