You have two adjustments you can make. High speed mix and low speed mix.
Both initial setting are 1 1/2 turns out from lightly seated. Once there you can fine tune both. I start with the high speed (under the bowl) and turn it clockwise until it starts to sputter, then counter clockwise just until it clears up. Bring your speed down to idle and do the same to the low speed mix on the side of your carburetor, and then one more final minor adjustment of the high speed.
I suspect you may have some water or debris or varnish in your carb bowl or on the jets themselves though. I would recommend removing and cleaning all before you adjust everything.