Install the latest wkhtmltopdf binary, extract it, and copy the wkhtmltopdf and wkhtmltoimage executables to /usr/bin/.
wget https://github.com/wkhtmltopdf/wkhtmltopdf/releases/download/0.12.4/wkhtmltox-0.12.4_linux-generic-amd64.tar.xz
tar xf wkhtmltox-0.12.4_linux-generic-amd64.tar.xz
cd ./wkhtmltox/bin/
sudo cp -R ./* /usr/bin/
wkhtmltopdf -VIf you get an error relating to libxrender1, fix it with:
sudo apt-get install libxrender1See also this gist.