Serious games are one of the new learning tools used to teach complex procedures which are costly and hard to reproduce in traditional practical trainings. In our research, we are interested in serious games that teach industrial procedures involving both software tutorials and real world operations. Our objective is to introduce an authoring tool which assists trainers to model their serious game scenarios (i.e. both the activities to be performed and the associated pedagogical feedback) with as much expressiveness and efficiency as possible. In order to reach this goal, we have implemented several automatic features. The main one is a process that allows trainers to record entire parts of the scenario directly from an existing virtual environment and domain specific software. Scenarios can finally be generated automatically in a specific graphical representation and then in a Domain Specific Modelling Language without the need of specific computing skills.