If you want to install nvidia drivers manually you need to read the documentation. In your case it is located here..
ftp://download.nvidia.com/XFree86/Linux-x86/260.19.21/README/index.html
However i think nvidia driver version 260.19.06 is in the ubuntu repositorys in the package nvidia-current which you can install easily via "apt-get install nvidia-current" if its not already installed.
Nvidia drivers are a closed binary and so we don't know what the installer does precisely and so its hard to tell what the pre-requisites are without reading the readme.