Select NasHyd command under the Hydgrographs section in the Tool Box.
Drag and drop the NasHyd command from the Tool Box to to the desire location (somewhere in the subcatchment) on the Schematic view. A new NasHyd will be created in the given location.
Click the NasHyd command on the Schematic view. Navigate to the Properties tab of the NasHyd command. Edit the parameters as shown below.