pretty_titles.tex

\usepackage{fancyhdr}      % Go for customized headings
\usepackage{titlesec}
\usepackage{sectsty}

\setlength{\oddsidemargin}{1.4cm}
\setlength{\evensidemargin}{1.4cm}
\setlength{\textwidth}{15cm}
\setlength{\topmargin}{10pt}

% Need these:
\setlength{\headheight}{10pt}
\setlength{\headsep}{20pt}

\setlength{\textheight}{23cm}
\setlength{\parindent}{0pt}
\setlength{\parskip}{\baselineskip}

% Sans section titles
\allsectionsfont{\sffamily}

\pagestyle{fancy}
\fancyhf{}                 
                                       
\lhead{\sffamily{\rightmark}}
\cfoot{\sffamily{\thepage}}
\renewcommand{\headrulewidth}{0.5pt}      
\renewcommand{\footrulewidth}{0.5pt}

\titleformat{\chapter}[display]
  {\sffamily\bfseries\Large}
  {\filleft\ \Huge\thechapter}
  {4ex}
  {\titlerule
   \vspace{2ex}%
   \filright}
  [\vspace{2ex}%
   \titlerule]