Hey, this is a question that's easily answered.

Try something.
And check to see if it helps or hurts.

Adjusting the idle is not really a mystery.
Start the engine and run it full throttle for a minute. Then do your idle test. Then shut 'er down. Turn the idle needle whichever way you think it needs it and run her again. Did it help or hurt? If you can't tell, repeat the same adjustment until you can tell. Then do what that tells you.

It's very complicated to write up all the ins and outs of idle-needle setting, but it's dead simple to do it. And it takes you almost no time to do it if you simply keep going in one direction until it's obvious if that's helping or hurting.

The only secret to it? Don't lose track of how much you've changed it. OK, there might be another. Don't stop changing until it's obvious the direction you're going is either right or wrong. Don't stop the first time you think it might have been better. Test the next step and see if it's still getting even better or even worse.

This is one deal that is better done than talked about. Just try something. You'll learn to do this far quicker trying stuff than reading stuff.