The manual provides future managers specialising in business informatics with a detailed introduction to enterprise architecture modelling technology. The free version of ADOit (Common edition), developed by the Austrian company BOC and widely used for enterprise management in many countries around the world, as well as for training managers at universities and business schools, is used as a software tool for enterprise architecture modelling. The choice of enterprise architecture modeling examples is determined by the relevance of tasks from various areas of managers' activities. The tasks of modelling small businesses, university, bank, specialised IT-oriented enterprises are considered here. The manual can also be useful for existing managers, who master and use the ADOit system.