1. Double-click the header on page 1.

2. On the Header & Footer menu that appears, select Different First Page.
   
   Select Close Header and Footer or press Esc to exit the header. 
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   Now, any changes you make to the header on the first page appear only on that page.

Tip: If you want to change the header on the rest of the pages, double-click the header on page 2 or later, and make the changes.