No technical expert advice can be found here ;)

Very often, software for OS X is provided as .pkg or .mpkg bundles (the difference is, that .mpkg bundles are more customizable than the .pkg-installers). If you want to install them without clicking through the GUI-user-dialog, you can do this by running the installer from the console in silent mode:

sudo -S installer -verbose -pkg your_installer_file.pkg -target /

The installer will run without showing something on the GUI. You will have to enter your system-administrators password, if the installer needs the rights. You can (but shouldn’t) give the password with the command line (so you can install .pkg in an automated way):

echo <password> | sudo -S installer -verbose -pkg your_installer_file.pkg -target /

||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Attention: Your password will be stored among other files in the bash_history!

||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||