Page numbering at bottom of page

Question

I am writing my thesis and I am using document class thesis. I want the page numbering appearing at bottom of the pages and centered.

\documentclass[12pt,a4paper, oneside, bold]{thesis}
\usepackage[left=3cm,right=2cm,top=3cm,bottom=2cm]{geometry}
\begin{document}
My text....
\end{document}

I tried writing something like that:

\documentclass[12pt,a4paper, oneside, bold]{thesis}
\usepackage[left=3cm,right=2cm,top=3cm,bottom=2cm]{geometry}
\usepackage{fancyhdr} 
\fancyhf{}
\cfoot{\thepage}

\begin{document}
    My text
\end{document}

But nothing is working. Any suggestions please.

Answer 1

The package fancyhdr allows you the modification of the header. However the package fancyhdr doesn't overwrite the default styles instead it defines a new one named fancy. So you have to use \pagestyle{fancy}:

\documentclass[12pt,a4paper, oneside, bold]{thesis}
\usepackage[left=3cm,right=2cm,top=3cm,bottom=2cm]{geometry}
\usepackage{fancyhdr} 
\fancyhf{}
\cfoot{\thepage}
\pagestyle{fancy}    
\begin{document}
    My text
\end{document}

Answer 2

Write in the header or body

\pagestyle{plain}

The \pagestyle command changes the style from the current page on throughout the remainder of your document.

The valid options are:

• plain - Just a plain page number.
• empty - Produces empty heads and feet - no page numbers.
• headings - Puts running headings on each page. The document style specifies what goes in the headings.
• myheadings - You specify what is to go in the heading with the \markboth or the \markright commands.

Pro: doesn't require additional packages.

Con: the author of the question actually used fancyhdr (I don't know the reason). Several people pointed that my answer in comments would be also useful, that is why I'm posting it here.

See more about page styles and fancyhdr in the Wikibook on LaTeX.