\mode<presentation>

%
% Load beamer settings
%
\usecolortheme{sigsum}
\usefonttheme{sigsum}
\useinnertheme{sigsum}
\useoutertheme{sigsum}

%
% Disable navigation tools on slides
%
\setbeamertemplate{navigation symbols}{}

%
% Object styles
%
\setbeamertemplate{itemize item}[square]
\setbeamertemplate{itemize subitem}[default]
\setbeamertemplate{sections/subsections in toc}[square]

\mode<all>