Adjusting circuit screws

So i have NEVER done this before. i tried fooling around with the pilot adjustment screws on my 1981 KZ1000LTD but i never fine tuned them. All 4 are set to 2 and half turns out.. if i can remember right. Anyways, when adjusting each screw, what do i listen for? Slight increase in RPM or decrease? im really just asking for an explanation on how to adjust them screws They are located in the front of each carburetor right on the top.

Thanks guys,
KT