Instructions
Navigate to the Jumpstationz website (see Resources) and click the "Make Carth a Jedi" mod-link. Click "Save File" when the pop-up menu appears and the mod will start downloading to your hard drive.
Double-click the file once the download is complete to open it. It is compressed in the "7Zip" format, so you will need either "7Zip" or "Universal Extractor" (see Resources) to open it.
Select the "Override" folder inside your "KOTOR" folder when asked to specify a path where you want to extract the files to. For example, if you installed the game to the default directory, the full path to extract the archive to would be "c:\program files\swkotor\override."
Start the game and travel to the planet Dantooine with Carth as a member of your party. Speak to Vor Zarran, a new NPC that the mod adds to the game. You'll find Vor Zarran in the courtyard of Dantooine near the character named Kni.
Speak to Vor Zarran and he will make Carth a Jedi. There is no option to exit the dialogue with him without Carth becoming a Jedi, so make sure this is what you want. Once Carth becomes a Jedi he will have a new robe and light saber.