turn it out, it's leaner, turn in its richer.
After you've establishe your jetting, give the bike a full shot of throttle then release, if it stumbles then revs up, turn it out , if it revs up nad hangs up a little before the revs fall, turn it in.
The screw fine tunes the pilot get, you want the revs to rise and fall smoothly.
If you have it almost all the way in, like 3/4 of a turn or under, it's time to go up a size on your pilot.
Also check out BenBB's jetting FAQ, it's an excellent sorce of info!!!!!