Throttle cable

Guys, I am very new to this forum and very impressed. I was actually wanting to start a forum just for ATV'ers with the Rincon, glad to see someone did it already! I read on someones thread but now I cant find that thread. They were talking about how there was slack in the Throttle cable. I checked mine and from pushing on the thumb lever while the machine is off it takes a good bit of movement before the cable engages the needle in the carborator. How do I adjust this. I looked under the rubber boot and didn't see any screw (as I belive someone had suggested). Is there something specific I should look for?

Also, Can I have the procedure again from someone on how to adjust it correctly, I am an Electrical Engineer not a mechanic, and therefore tend to screw up mechanical things very quickly (ie. I have broken many screws and bolts off into something by overtorqing). Thank you for your help in advace.