How to Add Custom Headers and Footers in LaTeX
The fix
Use the fancyhdr package. Load \usepackage{fancyhdr}, set \pagestyle{fancy}, clear defaults with \fancyhf{}, then fill the header with \lhead{}, \chead{}, \rhead{} and the footer with \lfoot{}, \cfoot{}, \rfoot{}. Use \leftmark and \rightmark for the current chapter/section, and \thepage for the page number.
Example
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhf{} % clear defaults
\rhead{\leftmark} % chapter name, right header
\lhead{My Thesis}
\cfoot{\thepage} % page number, centre footerFrequently asked questions
Why is there a line under my header?
fancyhdr draws a header rule by default. Remove it with \renewcommand{\headrulewidth}{0pt}, or set a larger value to thicken it.
How do I put the chapter title in the header?
Use \leftmark (chapter) or \rightmark (section) inside \rhead or \lhead. fancyhdr updates them automatically as the document progresses.
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