Personally, I would ask the Grandkid
I have a 97 Vulcan 500 LTD and the manual says:
Start the engine & warm it up thoroughly.
Turn the adjusting screw until idle speed (1,300 +/- 50 rpm) is correct.
Open & close the throttle a few times to make sure the idle speed is within the specified range. Readjust if necessary.
Doesn't say which direction to turn.
Also, how would you know the correct rpm for your bike, you got a tachometer?
Guess you'd just have to feel it out from how you know your bike feels and sounds.