I thought I gave you the procedure a while ago...maybe not...but here it is anyway, in the order it should be done in (though there are probably many ways to skin this cat):
1) Idle jet: with engine HOT, choke disengaged, float level correct, valve lash correct, and ignition timing correct, set idle to desired speed via idle speed screw. Slowly turn the idle mixture screw in or out until you find the fastest idle speed, or use a vacuum gauge to find the highest vacuum reading. Adjust the idle speed screw if necessary to get your preferred idle RPM. Adjust the mixture screw again if necessary to the highest speed and repeat the process until the idle is at your preferred speed. Turn the idle mixture screw in (clockwise) about 1/4 turn and turn the idle speed up via the idle speed screw if it drops significantly. Now shut off the engine and count the number of clockwise turns until the idle mixture screw is fully seated. It should be 1 3/4 to 2 turns. If it is less than that, your idle jet is too big, and if it is more than that, the idle jet is too small. The idle jet also handles progression from idle to low speed, so it needs to be big enough to feed a little fuel to the progression holes right below the throttle plate as the throttle starts to open.
2) Primary main jet: choose the smallest size that will run smoothly at low engine speeds on the primary throttle. This jet typically affects the range from right off idle to halfway through the RPM range that you encounter without getting into the secondary barrel.
3) Primary air corrector: chose the largest (larger = more air = leaner) size that will run smoothly through the higher engine speeds when on the primary barrel. This jet allows air to emulsify the fuel (mixes it into a froth, more or less) as air velocity through the carb increases, so its influence is on the mixture as engine speed and airflow increase. The main jet sets the base fuel delivery on that barrel, and the air corrector trims the fuel delivery at higher engine speeds.
At this point, the vehicle should be smooth and responsive on the primary barrel under any conditions. Once the primary side is sorted you can address the secondary, but the primary side MUST be sorted first. Also, there is an idle yet on the secondary barrel, but it doesn't do much and can typically be ignored.
4) Secondary main jet: choose the smallest* size that provides smooth performance as the secondary starts to open, and midway through the RPM band with the secondary barrel open. This is a good time to start reading plugs to make sure you have a "correct" air/fuel ratio. Going lean at WOT is usually not a good thing.
5) Secondary air corrector: choose the largest* size that provides smooth performance through the upper portion of the RPM range with the secondary throttle open. Again, reading spark plug colors or borrowing a wideband oxygen sensor are good ideas to make sure you have the mixture correct.
* For safety, you may want to choose one step richer (one step larger main jet, one step smaller air corrector) than the leanest that run smoothly for the secondary side. For durability, it's generally better to be a little rich than a little lean under WOT.
