From this website:
cd nvidia-graphics-drivers*
dpkg-buildpackage -us -uc -nc
cd ..
sudo dpkg -i nvidia-current-updates_*.deb

Let’s say we’re in the nvidia-graphics-drivers* dir.
In my case,
dpkg-buildpackage -us -uc -nc
hasn’t created the .deb file so after going cd .. I did this:

sudo dpkg-source -x nvidia-graphics-drivers-updates_295.49-0ubuntu0.1.dsc
cd nvidia-graphics-drivers*
sudo dpkg-buildpackage -rfakeroot -b
sudo dpkg -i nvidia-current-updates_*.deb