Go to this website. Fill out the required information. Fill out the information if you would like to register. (If you wish not to register, just scroll down to the end and click on the "I agree...." button. Choose an option and start downloading your file.
( The following instructions are good on Windows only. If you are using Linux or Solaris, I think it will be similar. ) The downloaded file is probably a zipped file (You never know if they will change it. When I downloaded it, it was a zipped file). You need to unzip and expand it to a desired directory. You should name your directory yourself (I named it Prolog). After expanding it, you could start exploring your directory.
If you want to start running Prolog, you should find a folder, or directory, named bin. Click on the file WideA.exe. This is the Interpreter/Compiler. A window will pop up. This program is basically an integrated editor-/compiler-/interpreter-.... thing. You can edit your own program and run it within this program. You do not have to switch windows. When you want to "execute" your program (maybe "test" would be more appropriate), choose Listener and then choose Start. Despite the fact that the program you just wrote is still in one of the windows you could see on the screen, you still need to "consult" the file. This tells the interpreter/compiler that you want your program to be loaded in to the memory and you want your interpreter to reason according to the evidence/inforamtion you gave in your program. You can consult your file by issuing a command consult('sample.pro'). You should really pay attention to the instruction. The ending period is necessary, or the interpreter will just wait for it.
Or you could choose the file via a graphical user interface by selecting "Consult" or "Reconsult" under "Listener". Ok, once you have successfully consulted your program, you should be debugging it yourself if it does not run.
If you develop your own program on your PC, after finishing programming, you should check if it runs on remus. There might be some slight difference between versions so you do not want to get points deducted just because you forget to check. Any program that does not run, regardless of your logic layoutin the program, will be penalized rather severly. Therefore, please make sure that your program runs on remus.