First break it in. If you don't do that first then your adjustments are not going to be right: Start the engine, go to 3/4 throttle and using the high speed needle (the one on the back) figure out where the engine transistions from a 4 cycle sound to a 2 cycle sound. Once you find that run the engine just past that transition. You want a rich 2 cycle sound. Run for 2 minutes then let it completely cool. Repeat the cooling and running until you have gone though 2 takes of fuel.

Now that it's broke in you can start tuning. Work on full throttle running first, start with the large screw on the back and turn it in to lean it up until you hear the engine hit it's peak rpm then turn it back out 3-4 clicks. Once you have it running correctly with full throttle then work on your transfer. Move your throttle up and down, it shouldn't hesitate or bog when you go from idle to full throttle. If it does and you get a puff of smoke that means that your idle mixture is too rich, no smoke means it's too lean. As buckskin points out the idle mixture is the little tiny screw inside the carb barrel. Start turning it (inward if it's too rich, outward if it's too lean) 1/16th of a turn at a time (restarting your engine every time) until you can go from full to idle back to full without it bogging.

I spent an hour tuning my engine to perfection after deadsticking my plane once and it made all of the difference.