The titlesec Package

\titleformat{\chapter}[display]
  {\normalfont\bfseries\color{gold}}
  {\filleft\hspace*{-60pt}%
    \rotatebox[origin=c]{90}{%
      \color{black}\Large%
        \normalfont\textsc\chaptertitlename%
    }\hspace{10pt}%
    {\setlength\fboxsep{0pt}%
    \colorbox{gold}{\parbox[c][3cm][c]{2.5cm}{%
      \centering\color{white}\fontsize{80}{90}\sansserif\thechapter}%
    }}%
  }
  {10pt}
  {\color{gold}\titlerule[2pt]\vskip3pt
  \color{black}\titlerule[1pt]\vskip4pt
  \color{gold}\huge\sansserif}


\titleformat{\section}
  {\sansserif\Large\bfseries\color{mygray}}
  {\thesection}{1em}{}

\titleformat{\subsection}
  {\color{darkgray}\sansserif\large\bfseries}
  {\thesubsection}{1em}{}

  \titleformat{\subsubsection}
  {\sansserif\bfseries}
  {\thesubsection}{1em}{}{}