Dear Grandpa: First, turn off CapsLock. Using all caps is the equivalent of
shouting - not polite.
Assuming your printer has a bypass tray with adjustable guides for odd-sized
paper, proceed as follows:
In Word 2007, Click on Page Layout, Size, More Paper Sizes.
In earlier versions:
Click File, Page Setup, Paper Size
In all versions:
On the next dialog, drop the paper size dropdown and select Custom
Enter Width and Height as appopriate.
Click OK.
Now you will have a page of the desired size on which to enter text.
Place a stack of index cards in the printer's bypass tray and print away.