Such a grid of boxes can be easily achieved with tcbraster from tcolorbox, a marvellous package.
Define a tcbraster environment with the relevant data (4 rows, 4 columns), set the height and an eventual spacing)
Define a special \posterbox command for the content, the numbers in the background can be achieved with an underlay and TikZ statement.
The coloured background boxes can be achieved with special styles, predefined.
\documentclass{article}
\usepackage{blindtext}
\usepackage[landscape,a1paper,margin=2cm]{geometry}
\usepackage[dvipsnames,x11names, svgnames]{xcolor}
\usepackage[most]{tcolorbox}
\tcbset{bluebox/.style={colback=DarkSlateGray1},whitebox/.style={colback=white}}
\newtcbox[auto counter]{\posterbox}[2][]{%
fontupper={\LARGE\bfseries},
enhanced jigsaw,
sharp corners,
colframe={blue},
nobeforeafter,
underlay={\node[scale=10,opacity=0.3] (A) at (interior) {\huge #2}; },
whitebox,
#1,
}
\begin{document}
\begin{tcbraster}[raster columns=4, raster equal height,raster column skip=2pt,raster height=\textheight, raster rows=4]
\posterbox{1}{\blindtext}
\posterbox[bluebox]{2}{\blindtext}
\posterbox{3}{\blindtext}
\posterbox{4}{\blindtext}
% 2nd row
\posterbox{2}{\blindtext[2]}
\posterbox{3}{\blindtext}
\posterbox{4}{\blindtext}
\posterbox[bluebox]{1}{\blindtext}
% 3rd row
\posterbox{3}{\blindtext[3]}
\posterbox{4}{\blindtext}
\posterbox[bluebox]{1}{\blindtext}
\posterbox{2}{\blindtext}
% 4th row
\posterbox[bluebox]{4}{\blindtext}
\posterbox{3}{\blindtext}
\posterbox{2}{\blindtext}
\posterbox{1}{\blindtext}
\end{tcbraster}
\end{document}

Original version
\documentclass{article}
\usepackage{blindtext}
\usepackage[a0paper,margin=2cm]{geometry}
\usepackage[most]{tcolorbox}
\newtcbox[auto counter]{\posterbox}[1][]{%
fontupper={\LARGE\bfseries},
enhanced jigsaw,
sharp corners,
colback={white!90!yellow},
colframe={blue},
nobeforeafter,
underlay={\node[scale=10,opacity=0.3] (A) at (interior) {\huge\thetcbcounter}; },
#1
}
\begin{document}
\begin{tcbraster}[raster columns=4, raster equal height,raster column skip=2pt,raster height=\textheight, raster rows=4]
\posterbox{\blindtext}
\posterbox{\blindtext}
\posterbox{\blindtext}
\posterbox{\blindtext}
% 2nd row
\posterbox[colback=yellow]{\blindtext[2]}
\posterbox{\blindtext}
\posterbox{\blindtext}
\posterbox{\blindtext}
% 3rd row
\posterbox{\blindtext[3]}
\posterbox{\blindtext}
\posterbox{\blindtext}
\posterbox{\blindtext}
% 4th row
\posterbox{\blindtext}
\posterbox{\blindtext}
\posterbox{\blindtext}
\posterbox{\blindtext}
\end{tcbraster}
\end{document}

1in a box mean that it is meant for all boxes numbered this way, i.e. the content is the same for all this boxes, etc.? Welcome to TeX.SE, by the way. I thinktcbrastersfrom thetcolorboxpackage might be a method... – Jan 01 '17 at 22:46