%%
%% The LaTeX Companion, 3ed
%%
%% Example 4-1-13 on page I-266 in "The general formatting of the list environment body".
%%
%% 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{171.0pt}

  \usepackage{microtype} % to help as the example in the book is so small
%StartShownPreambleCommands
\usepackage{enumitem}
\setlist{rightmargin=0pt}    % already the default
\setlist[1]{rightmargin=20pt}
%StopShownPreambleCommands

\begin{document}
A sample text showing the outer margins of
normal text.
\begin{itemize}
\item A sample text of more than one line please.
  \begin{itemize}
  \item A sample text of more than one line.
    \begin{enumerate}
    \item A longer sample text with two lines.
\end{enumerate} \end{itemize} \end{itemize}
Again some more text to indicate the galley margins.
\begin{description}
\item[Description test] A longer sample text with
   two lines of text.             \end{description}
\end{document}