Both as a professional traffic controller and as an event traffic controller, it is not allowed to give directions in or from a vehicle. First park the vehicle in a safe place and walk to the place from where the directions are to be given. When you are moving with the vehicle, you are not allowed to wear traffic controller’s clothing. As a professional / event traffic controller you are not authorized to do this. Only the police, military police, transport escorts and road inspectors from Rijkswaterstaat are authorized to give directions from or from a (motor) vehicle.
The general stop sign is given with the right hand. This direction is also examined during the professional traffic controller exam. The police has determined the requirements for giving directions. In appendix 2 of the Reglement Verkeersregels en Verkeerstekens 1990 (RVV 1990) you can find all established gestures and directions.