There is no adjustment on a master/slave hydraulic clutch system. It is self adjusting every time you release the pedal, the hydraulic fluid is released back into the reservoir and pressured equalize, just like the brakes. However you can diagnose problems usually quite easily based on the symptoms. If the clutch pedal will not disengage the clutch, then the master or slave cylinders are bad. It could also be caused by low clutch hydraulic fluid, but the system does not consume fluid so if it is low then there is a leak, usually at the master or slave cylinders, so we are back to the first answer again. If the clutch will disengage but will not engage properly, (slipping) then the clutch disc is worn out. If you have to pump the pedal several times for it to work then their is likely air in the system that needs to be bled out, but this condition would lead to the next logical question, "how did air get in the system"? and would have to be answered, and would probably be due to low fluid, due to a leak, due to a bad master or slave. SO, you really have two choices. A bad master or slave or a worn out disc depending on if it wont engage or wont disengage. Forget about adjusting it because you can't!