How do I get margin notes to appear on the left?

Question

I'm trying to make a left-sided margin note.

As per the LaTeX wiki, I tried using \reversemarginpar but that didn't solve anything—it didn't make a margin note at all. I also tried \marginpar[left text/right text]{%my text} to no avail. I tried using two other packages, marginnote and mparhack, but again, those didn't solve my problem.

Maybe there are some things I've missed (perhaps I have to further define something in the preamble?), but I would appreciate an example of how to use a margin note successfully.

Here's some code I tried:

\documentclass{article}

\usepackage{amssymb}
\usepackage{wasysym}
\usepackage[top=2cm, bottom=1.3cm, left=2.5cm, right=2.5cm]{geometry}
\usepackage{tensor}
\usepackage{enumitem}
\usepackage{outlines}
\usepackage{ulem}

\title{Chapter 13 - Chromosomal Rearrangements and Changes in Chromosome Number}
\author{A. Uthor}
\date{}

\pagestyle{empty}

\begin{document}
  \maketitle

  \section*{\Large Types:}
  \begin{outline}[enumerate]
  \1 Duplications
  \1 Deletions
  \1 Inversions
  \1 Translocations
  \end{outline}

  \textbf{semisterility} $\rightarrow$ diminished fertility of translocation heterozygotes by at least 50\%
  \reversemarginpar{Why does Mendel's 2$\mathrm{^{nd}}$ require viability of offspring?}
\end{document}

Answer 1

The \reversemarginpar command cannot be used to typeset the marginal notes; as Willie Wong mentioned in a comment, all \reversemarginpar does is to force all subsequent marginal notes to be put on the opposite side. To typeset your marginal notes, you can use the standard \marginpar command or, even better, you can use the \marginnote command provided by the marginnote package: an example including some of your code:

\documentclass{article}
\usepackage{amssymb}
\usepackage{wasysym}
\usepackage[top=2cm, bottom=1.3cm, left=2.5cm, right=2.5cm]{geometry}
\usepackage{tensor}
\usepackage{enumitem}
\usepackage{outlines}
\usepackage{ulem}
\usepackage{marginnote}

\reversemarginpar

\title{\vspace{-0.9in}\uline{Chapter 13 - Chromosomal Rearrangements and Changes in Chromosome Number}}
\author{A. Uthor}
\date{}  

\begin{document}

\section*{\Large Types:}
\begin{outline}[enumerate]
\1 Duplications
\1 Deletions
\1 Inversions
\1 Translocations
\end{outline}

 \textbf{semisterility} $\rightarrow$ diminished fertility of translocation heterozygotes by at least 50\% \marginnote{Why does Mendel's 2$\mathrm{^{nd}}$ require viability of offspring?}

\end{document}

You must compile several times to see the marginal note in its final position.

On a side note, can I ask you why do you use the outlines package? It is not part of TeX Live or MiKTeX, and the enumitem package (which you are also loading) offers you more possibilities (in my opinion) to customize your lists.