\makeatletter % the 'at' sign is now a normal "letter" for TeX
% Redefine the \section{} and \subsection{} to be smaller and use less space:
\renewcommand{\section}{\@startsection
{section}% % the name
{1}% % the level
{0em}% % the indent
{-0.10\baselineskip}% % the beforeskip
{0.25\baselineskip}% % the afterskip
{\normalfont\large\bfseries}}% % the style
\renewcommand{\subsection}{\@startsection
{subsection}% % the name
{2}% % the level
{1em}% % the indent
{-0.25\baselineskip}% % the beforeskip
{0.10\baselineskip}% % the afterskip
{\normalfont\bfseries}}% % the style
\makeatother % the 'at' sign is restored as a "non-letter" for TeX