create last revised watermark on latex memo

insert_date.tex

\usepackage[]{gitinfo2}
\begin{document}

\begin{tikzpicture}[remember picture,overlay]
        \node at ([xshift=3cm,yshift=2cm]current page.south west) {\tiny \color[gray]{.8} Last Revised: \gitAuthorDate};    %% yshift and xshift for example only
\end{tikzpicture}

\end{document}