Canon PIXM MX300 Series User Manual page 27

Note
When performing copy direct printing without using a computer,
select the size and type of the loaded paper using the Operation Panel.
For details on settings, see
the Print Settings.
When using the machine connected to a computer, select the size
and type of the loaded paper in Page Size (or Paper Size) and
Media Type in the printer driver.
For details on printer driver settings, see
Printing with Macintosh.
Changing the Copy Settings
Printing with Windows
27
or Changing
or