You will need Half-Life installed on your computer.
Unzip the files in the Valve directory.
The other files must be copied to the correct locations in your Half-Life directories. These directories should all be found in the Half-Life directory within the Sierra directory within your C drive, but may be elsewhere, depending on your version of Windows.
Copy the .wad files to the Valve directory.
Copy files in the SAVE directory to the SAVE directory in your Half-Life installation.
Note: create a SAVE directory if there is not currently one in the Half-Life directory.
Copy the map files into the Maps directory of your Half Life installation.
To play "New Word Order: Basra," start up Half-Life. At the Main Menu, go to Load Saved Game. Select either of the saved games to load the map.
Play the game.
Note: the mod was designed for the original Half-Life and has not been tested with Half-Life 2 or Half-Life Source.

The basra.mov file documents the mod. Click video button to watch.

The Nihilanth: Immersivity in a First-Person Gaming Mod (pdf).