A civil engineering machine has a machine control unit configured to determine data which defines the position and/or orientation of a reference point on the civil engineering machine in relation to a reference system independent of the position and orientation of the civil engineering machine. A geometrical shape to be produced on the ground is preset in either a machine control unit or a field rover control unit. The field rover is used to determine a position of at least one identifiable point of the preset geometrical shape in the independent reference system. Curve data defining a desired curve in the independent reference system, corresponding to the preset shape, is determined at least partially on the basis of the position of the at least one identifiable point of the preset geometrical shape in the independent reference system.