I am about to submit an article for review, and had to format in a special way. Here is a quick summary of what I did:
No paragraph indents:
\setlength{\parindent}{0in}
but a single line between:
\usepackage{parskip}
Left text justification:
\begin{flushleft} ... \end{flushleft}
Double spacing:
\renewcommand{\baselinestretch}{2}