There are four software packages related to the Nightingale Tracker. Locate the the desired version of the desired software package from the list of downloads. These instructions will include the pertinent RPM commands, but it would be a good idea to review the docs to review the topic if it is not familiar to you. Use your browser to download the desired file and save it to disk. On some browsers if you click on the link to the file, the browser will attempt to display the file, or worse crash because it thinks the file needs to be played with the Real Audio Player.
Most browsers have a way to specify the file associated with the link needs to be saved to disk.
Since there are more browsers out there than I can count, you'll have to figure the subtleties of this step out yourself. At least those are methods I've found in the past. Once the package has been saved to disk, you must transfer it to your server. If your server is on the network, you can FTP the file. If not, you're probably going to end up using a floppy.