Personally, I wouldn't. There are several inexpensive programs dedicated to
making greeting cards, and they handle the job much better than Word can, in
addition to offering artwork and sample wording.
If you insist, you can lay out a quarter-fold card by using the method
described in http://word.mvps.org/FAQs/DrwGrphcs/UpsideDownText.htm. The
outside of the card faces one way, and the inside pages face the other way.
