The following code is very interesting as it adds an asterisk beside an enumeration.
\documentclass{article}
\usepackage{enumitem}
%%%%%%%%%%%%%%%%%%%%%%%%
%% CODE thanks to egreg
%%%%%%%%%%%%%%%%%%%%%%%
\setlist[enumerate]{before=\setupmodenumerate}
\newif\ifmoditem
\newcommand{\setupmodenumerate}{%
\global\moditemfalse
\let\origmakelabel\makelabel
\def\moditem##1{\global\moditemtrue\def\mesymbol{##1}\item}%
\def\makelabel##1{%
\origmakelabel{\ifmoditem\llap{\mesymbol\enspace}\fi##1}%
\global\moditemfalse}%
}
\begin{document}
\begin{enumerate}
\moditem{*} test
\end{enumerate}
\end{document}
This yields:

My question is:
"How can I create a similar modded item, say \citem, that colours the enumeration?"
A similar code or using the idea as above would be great. Note that the colouring (what the user wishes to be) must be to selective items and not the entire set of enumeration.
UPDATE: So looking at the links above I thought I had the solution as the code;
\newcommand{\myitem}{\refstepcounter{enumi}\item[\color{red}{\theenumi.}]}
sheds some light, but it does not respect enumeration within enumeration. Hmmmmmm???

This is given by
\begin{enumerate}
\myitem
\moditem{*} test
\myitem
\myitem Test test test
\begin{enumerate}
\item
\item
\item
\myitem
\end{enumerate}
\end{enumerate}

\colorevery item, setting to black in the default case. – David Carlisle Sep 27 '12 at 15:59