Are these individual postcards?
If they are and the printer will accept the page size, then printing on a
card is like printing any other document. If as I suspect the printer does
not have the card size defined then set the page size to the next larger
standard size and set the margins to define the available text area.
If they are not individual postcards, use the envelope/label wizard and pick
the corresponding 'label'.
--
<>>< ><<> ><<> <>>< ><<> <>>< <>><<>
Graham Mayor - Word MVP
My web site
www.gmayor.com
<>>< ><<> ><<> <>>< ><<> <>>< <>><<>