# Custom header: [E] \chaptername \thechapter [O] \chaptermark

I'm new here and I'm into headers with package fancyhdr. My request is: I want on even pages, CHAPTER NUMBER, in the odd pages CHAPTERTITLE. So in a way like: [E] \chaptername \thechapter [O] \chaptermark

I face some issues with \renewcommand on \leftmark and \rightmark that I cant't edit both entry simoultaneously. Do you have any suggestions? Thanks

    \documentclass[a4paper,12pt,twoside,titlepage,openright,fleqn,onecolumn,draft]{book}
\usepackage[a4paper,top=2.5cm,bottom=2.5cm,left=2.5cm,right=2.5cm, bindingoffset=5mm]{geometry}
\usepackage{lastpage}
\usepackage{fancyhdr}
\fancypagestyle{plain}{%
\fancyhf{}

\pagestyle{fancy}
\fancyhf{}
\renewcommand\chaptermark[1]{%
\markboth{\MakeUppercase{\chaptername\ \thechapter}}{#1}}

\usepackage{blindtext}

\begin{document}
\chapter{CCC1}
\Blindtext\Blindtext\Blindtext
\section{SS1}
\Blindtext\Blindtext\Blindtext
\chapter{CCC2}
\Blindtext\Blindtext\Blindtext
\section{SS2}
\Blindtext\Blindtext\Blindtext
\end{document}

• Welcome to TeX.SX! A tip: You can use backticks  to mark your inline code. Could you please provide a minimal working example (MWE) so that we could help you more easily? – ebosi Apr 19 '16 at 12:40
• It would help if you could specify where the relevant pieces should appear. Left, centered or right? – user31729 Apr 19 '16 at 12:47
• Sure, i'm adding a few code lines. i'm feeling a newbie =( – Chris Apr 19 '16 at 12:47
• Don't worry: we've all started at the beginning, and you're here at the right place for your questions! – ebosi Apr 19 '16 at 12:56
• You want following hearder, don't you? [2n]_____Chapter X_|_Chapter-Name_______[2n+1] – ebosi Apr 19 '16 at 12:59

the answer provided by Christian Hupfer solves, in a specific way, the issue. But when I've added nomenclature nomencl and bibliography bibtex, headings become painful. So I discovered \usepackage{titleps}, instead of fancyhdr that provide simple solution: set up plain and main` pagestyle and other styles builded up eg. for nomenclature and bibliography , changing pagestyle whenever you want.