\usepackage{newtxtext} %
\usepackage{newtxmath} % selects Times Roman as basic font
\usepackage{diagbox}
+\usepackage{adjustbox}
+
+\newcommand{\turn}[3][10em]{% \turn[<width>]{<angle>}{<stuff>}
+ \rlap{\rotatebox{#2}{\begin{varwidth}[t]{#1}\bfseries#3\end{varwidth}}}%
+}
+
+\newcolumntype{C}[1]{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
% see the list of further useful packages
% in the Reference Guide