Here's the link to the MX-TECH tuning guide. They have an excellent step by step procedure that will help you tune your suspension for your specifics needs. Using someone else's settings rarely works well.
Now would that be #1 stones or #6 stone? ;)
Sorry but couldn't resist and I am curious what 12 stone is in pounds (and not that funny money)
The strange twists of international posts :cool:
As rich said you need to find what works for you on your bike and that MX Tech link is a great place to start
Also this is a 6 year old bike. I would seriously do a rebuild of the forks and shock before doing much else. A complete revalve for the suspension would be a good investment.