This example illustrates the symmetry operators for the ammonia molecule. The buttons perform the operations indicated. They work in local molecular axes, so even if the molecule is rotated they will appear to leave the molecular framework unchanged. The little yellow dot allows you to keep track of the operations. You will probably find it easiest to leave the molecule in its original configuration and just use the buttons.
It is conventional to take the C3 axis vertical, coinciding with the z axis of coordinates, so in this view you are looking down the z axis.