Neuromuscular electrical stimulation (NMES) is used to enhance muscle activity and circulation, particularly in individuals with reduced mobility. To improve treatment adherence, solutions must be comfortable, easy to use, and technically reliable. This thesis project, conducted in collaboration with Matrix Muscle Support (MMS), aims to develop an improved electrode patch and fixation solution for NMES treatment of the calf muscles.The project includes needs analysis, concept development, CAD-based design, and testing of two patch prototypes, one with 16 electrodes and one with 9. The fixation system was developed with a focus on ergonomics and self-application. Both patches and the fixation solution were designed using flexible materials, robust connection to the control module, and optimized electrode placement.The results show that the developed concepts meet high standards for function, usability, and manufacturability. The work contributes concrete improvements in product design and provides a foundation for further development and clinical validation of the system.