Vacuum Testing Question Help

[robroy55]

HI Folks !!
I have a actron III Vacumme & Pressure Tester kit. I have a vacuum leak some where in the car that makes the engine miss when first starting up and gets worse when I put the air on but only at idle. Once I get going, the car runs great. Gas millage is only 16 mpg around town with out air on. I have a 2002 24 valve engine with 37K.
My question is..... How do I use this tester?? When looking at the engine from the front of the car, what can I hook this tester up to and where would this hook up be located on the engine with the tubing that came with the unit Does the engine have to be running while testing? I would assum that while testing, if the needle does not hold steady, I have a vacumm leak. Now, if I do see the needle droping and not holding, how do I go about finding the leak??

Please don't laugh so hard as I am a newbie don't know about vacumm problems.

Thank for any help and step by step instructione anyone can give me with this matter