I think you're referring to the flower nut. It's held on by a tiny screw and is pretty much the only clutch adjustment there is (aside from the cable tension).
Anyway, pull the clutch lever and pin it. Tighten the flower nut with your fingers until it stops. Again, use your fingers, not tools. Once tight, position the nut to allow the tiny screw to be reinstalled (I use blue loctite here). Put it all back together and enjoy.