In recent years, interest in digital twins (DTs) has increased among both industry and academia. Consequently, various methods have been proposed to enhance the development and maintenance of DTs. The creation of DTs relies on integrating models and data from a variety of sources, including sensors, Internet of Things (IoT) devices, and other data streams. Model-driven engineering (MDE) is considered an effective approach for developing IoT applications. Previous research indicates that current methods focus primarily on software and systems perspectives, often overlooking the importance of organizational integration. Additionally, there is a growing need for approaches specifically designed to meet the needs of small and medium-sized enterprises (SMEs). This thesis project aims to develop (i) a method that includes clearly defined steps, (ii) a tool to assist SMEs in developing IoT-based DTs, and (iii) consider aspects of organizational integration in and following the development process.