fancyheadings.sty in a
directory/folder where / can find it (normally in the input
directory/folder), and include in the preamble of your document
after
\documentclass{...}
the commands:
\usepackage{fancyheadings}
\pagestyle{fancy}
We can visualize the page layout we can create with fancyheadings as follows:
LeftHeader
CenteredHeaderRightHeader
page body
LeftFooter
CenteredFooterRightFooter
The LeftHeader and LeftFooter are left justified; the CenteredHeader and CenteredFooter are centered; the RightHeader and RightFooter are right justified.
We define each of the six ``fields'' and the two decorative lines separately.