Hi, Al. This is pretty easy to do and darned difficult to describe. I have tried to before and it was only slightly a disaster. Basically what it amounts to is taking the rise and dividing by the number of steps and setting that on your framing square and doing the same thing with the run and the tread width. You can then mark your stringers for cutting.
I suggest that you get a book out of the library where they have the space to lay out the process and can also show you in pictures. Henry