See the following pages of Greg Maxey's website :
http://gregmaxey.mvps.org/Create_and_employ_a_UserForm.htm
To have the header display only on the first page of the document, you need to click the
Different First Page box in the Options section of the
Header & Footer Tools>Design tab of the ribbon. That tab will become available when you have the selection in the Header\Footer area of the document.
The setting can also be implemented via the
Layout tab of the Page Setup dialog accessed by clicking on the dialog launcher at the right hand end of the
Page Setup section of the Page Layout tab of the ribbon