Use the bypass tray to copy onto paper of a size that cannot be loaded in the paper trays.
About how to load paper in the bypass tray, see Paper Specifications and Adding Paper for details.
If the paper type you want to copy onto is not shown on the [Paper Type] screen, you must specify the paper type under [Tray Paper Settings] in User Tools. For details, see "Tray Paper Settings", Connecting the Machine/System Settings.