1) Open the zipfile
JailbreakIII-Gold.zip.
If you have XP you can open it directly, otherwise you have to use
WinZip.
2) Doubleclick on the file
JailbreakIII-Gold.umod
Umods are Unreal Tournament install-files.
It then will come up with the installer. In one screen you will be asked in what directory you want to install the files in. Most of the time this automatically points to your UT directory already. If not, fill in your UT-directory youself (eg. C:\UT).
Press next a couple of times, and that's really it.
Remark 1: Don't forget to download and install the
extra mappacks the same way as described above.
Remark 2: If doubleclicking the umod-file doesn't open the installer automatically, the file associations in your windows registry are probably messed up. You can download
this registry patch and doubleclick on it to repair this.
Remark 3: You also need to have
UTPatch v436, Unreal BonusPack1 and Unreal BonusPack4 installed. These were part of the Unreal Tournament GOTY Edition, but not of the original UT. If you don't already have them, you can get them
here
If you don't succeed, let us know.