Now that you have scanned the form or other document, open a new, blank Word document. Get to the document's header by going to the Insert tab in Word 2007 and clicking on Header. In Word 2003, go to the View menu and select Header and Footer. Click inside the header section on the blank Word document. In Word 2007, go to the Insert tab and select Picture in the Illustrations group. In Word 2003, go to the Insert menu, point to Picture and click From File.

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Locate the scanned document on your computer and insert it as a picture into the header. Use the ruler to move the margins, if necessary, and drag the scanned document so that it covers the majority of the Word document.