Canon LBP7780CX User Manual page 272

NOTE
The default setting for [Print Style] is [2-sided printing]. You can save the 1-sided printing setting as a preset. For details,
see "Using [Presets] for
3.
Select the binding edge from [Binding Location].
The output image is displayed in the preview area.
4.
If you want to set the gutter width, click [Gutter].
Printing."