Firstly, welcome to the forum.
This link from
Novell details the procedure and appears to spell it out fairly seamlessly.
If I mention that Google is your friend, and that "disk quota" is a good search string, it will come as no surprise to you how I came across what I believe to be the answer to your problem.
Good luck, I'm sure that there is further assistance here should you require it. Pop back and let others know how you faired and any issues or tips you might have to share as a result of your experience.
