Canon MF6180dw Manual page 220

3. Close the lower rear cover.
2
Place your document.
"Placing Documents"
"Supported Document Types"
3
Press [ ].
4
Press [ ] (2-Sided).
You can display the setting screen also by selecting <2-Sided> in the copy mode screen.
5
Select <1->2-Sided> using [
To specify the 2-Sided copy format
(1) Select <Format Settings> using [
(2) Select <1->2-Sided> using [
(3) Select the orientation of the original using [
] or [ ] and press [OK].
] or [ ] and press [OK].
] or [ ] and press [OK].
] or [ ] and press [OK].