# How do I change the way section headings look? [duplicate]

I have a few sections in my document that look like

\section*{Introduction}

The font size seems slightly too big for me, and I would like to make it smaller. I found the following \renewcommand snippet (link here):

\renewcommand{\section}{\@startsection
{section}%                      %the name
{1}%                            %the level
{0mm}%                          %the indent
{-\baselineskip}%               %the before skip
{0.5\baselineskip}%             %the after skip
{\normalfont\large\itshape}}%   %the style

But I get the error

You can't use `\spacefactor' in vertical mode

How would I go about solving this problem?

Thank you,

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