How to set the water softener...what does it all mean?

Can anyone tell me how to set this thing? It was in the house when we bought it years ago. We used it for awhile, but it seemed to be using waaaaaaaay more salt than it should, so assuming it was set incorrectly, we shut it off.

Our home has three full time occupants, and our city's water hardness is 240 mg/l.

I have NO idea what to do with these controls...

http://www.plumbingforums.com/photo/water50-385.html

I think that head is a Lyndsey (sp). I'm quite sure they made heads for Sears. You might look there for a booklet on how that head works. The only adjustments on older heads was what days of the week you wanted it to backwash and how many lbs of salt you wanted it to use. (Generally 9 to 12 lbs.) That setting is generally in the back of the head.

Problem with the old heads was they didn't know when to backwash. They just backwashed on the days you set it to. Newer heads count gallons and only regenerate when needed.