When I go to printers, printing options, there isn't an option to set reverse order as default.
How to do it?
If you're using CUPS, you want select "Printers" on the top menu bar, then select the printer you're interested in from the displayed list. Select the "Administration" button which reveals a pull-down menu (not Administration in the top menu bar). In the pull-down menu, select "Set Default Options." This reveals several option categories between two horizontal lines. Select "Printer Features Common." This reveals a new page of several features. Select the pull down menu next to "Orientation." From the pull down menu, select the option "Reverse Portrait" (or "Reverse Landscape" if that is your preference). Click on the button "Set Default Options." That's it. You can close CUPS or leave it open as you prefer.