Print From Your Computer : Macintosh Printing (OS X 10.5)

Select Page Setup Options
Depending on your application, you may be able to select the paper size and orientation settings from the Print window.
Note:
If you don’t see these settings in the Print window, check for them in your application before printing. For example, you may be able to open the File menu and select Page Setup.
1.
Select the Paper Size setting for the paper you loaded. A custom option is also available so you can create a custom paper size.
If you want to print a borderless photo, select the paper size with a Borderless option.
Note:
For borderless photos, make sure you loaded a compatible borderless paper size and type.
2.
Choose portrait or landscape Orientation for your document or photo. (Choose landscape for envelopes.)