%%
%% The LaTeX Companion, 3ed
%%
%% Example 3-5-15 on page I-214 in "footmisc --- Various footnotes styles".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{207.0pt}
\setlength\textheight{6.5\baselineskip}
\addtolength\textwidth{-80pt}
\setlength\marginparwidth{72pt}

%StartShownPreambleCommands
 \usepackage[side,ragged]{footmisc}
 \setlength\footnotemargin{5pt}
%StopShownPreambleCommands

\begin{document}
 A lot of additional text here to fill
 up\footnote{In the margin ragged
   right often looks best. Do you agree?}
 the space in the example. Include some
 text with a footnote and some more.
\end{document}