Yo Yo Yo,
2strokes have to be HOT in order to make them idle reliably.
Once the bike is HOT HOT HOT
Turn IN the idle screw until the idle is high.
With the bike idling too high, I adjust the air screw until the idle speed peaks, (1-1/2 turns from seated to start) and turn the screw IN 1/8th turn from the idle peak.
Turn the Idle screw OUT until the idle speed is as desired.
Usually takes a few whacks of the throttle to get it to normalize when adjusting idle mixture.
Good Luck -BIG DAN