The shift from product-oriented to service-oriented business requires a rethink, especially in traditional companies in the mechanical and plant engineering industry. This guideline for the development of Smart Services is intended to illustrate the complexity and thus improve their handling, supporting the planning and modelling of a Smart Service. The Design Thinking Process is the first step in understanding the challenges associated with the reorientation of the business and in designing appropriate solutions. In the second step, an important part of the rethinking process of companies is the proactive development, revision or complete redesign of their business models. The third part of this guideline is the concept of agile service engineering with support of artificial intelligence, which can be understood as a link between the design thinking process and business model development and can be used as a management tool.