How to add bullets to description lists?

One quick way is to do it manually for each bullet:

\begin{description}
  \item[$\cdot$ bla1] item 1
  \item[$\bullet$ bla2] item 2
  \item[$\ast$ bla3] item 3
\end{description}

This produces:

It would probably be better if you create your own list type using enumitem's \newlist feature.

If you don't want to do so, here's a hack, but it is somehow maintainable: Use the enumitem package and do the following:

\begin{description}[font=$\bullet$\scshape\bfseries]

That is, you encode the special stuff in the thing that should be your font, but it works fine, as long as the $\bullet (or equivalent) is in front of the actual description label.

---

\documentclass[twocolumn]{article}
\usepackage{blindtext}
\usepackage{enumitem}
\usepackage{xcolor}
\begin{document}
\blindtext Coco likes fruit. Her favorites are:
\begin{description}[font=$\bullet$~\normalfont\scshape\color{red!50!black}]
\item [Bananas] yellow and banana shaped
\item [Apples] red and round
\item [Oranges] orange and round
\item [Lemons] yellow, kinda round
\end{description}
\blindtext
\end{document}

You can use the itemization function (https://www.sharelatex.com/learn/Lists)

\begin{itemize}

\item one.

\item two. 

\item three.

\end{itemize}

And the output: