Press [Dup./Combine/Series].
Press [Series/Poster].
Select [2 Sided 1 Sided] or [Spread1 Sided].
To select [Spread1 Sided], press [Original Orientation], and then select the readable orientation for the original orientation beforehand.
Press [OK].
If you specified [2 Sided 1 Sided], you can specify the orientation. For details, see Specifying the Original and Copy Orientation.