How to Add Custom Paper Sizes to the MS Office Page Setup

1). Go to the "Page Layout" tab in Word 2007. Click "Size" and then "More Paper Sizes" to enter "Page Setup." You should land on the "Paper" tab.

In earlier versions of Word, click "File" on the top menu and select "Page Setup." You should again land on the "Paper" tab.
2). Click the drop-down arrow under "Paper size:" and select "Custom size" at the bottom.
3). Enter your desired "Height" and "Width" via the side arrows or your keyboard. Click "Default" at the bottom to use this size every time Word starts. Click "OK," and the display adjusts to your inputted sizes.
4). Click the Word 2007 orb in the top left corner of your screen. Hover over "Save As" and click "Word Template" on the pop-up. This enables you to save the setup as a template for later use.

In earlier versions of Word, click "File" on the top menu. Select "Save As" and then "Document Template."