I tried two of the solutions given on this forum. Neither of them really center the text. I put one below. It's off by quite a bit. I'd like it centered measuring from the textblock(?...the rectangle where the normal text is written) to the middle of the letter height (the capital letter is fine).
%\documentclass[a4paper, 11pt, oneside]{book} % A4 paper size, default 11pt font size and oneside for equal margins
%PACKAGES
\usepackage{fontspec}
\usepackage{libertine}
\usepackage{fancyhdr}
\usepackage[paperwidth=6in, paperheight=9in, showframe]{geometry}
\fancypagestyle{clearstyle}{\fancyhead{}\fancyfoot{}}
\begin{document}
\begin{center}
\vspace*{\stretch{1}}
{\Huge \textbf{\textit{Too Low}}\par}
\vspace*{\stretch{1}}
\end{center}
\clearpage
\end{document}




eso-pic. – Werner Mar 22 '20 at 21:31