What type of kettle do you have ? One touch clean out ?
The adjustment on the one touch system is very small . It only takes small adjustments to change the temp . Set up your fire and let it settle in . Mine likes to run around 250 , so that's my temp for smoking .
I add the meat with all the vents full open . See how adding the meat affects the temp . Give it time to recover . If it starts to climb , start closing the bottom vent 1/4 " at a time . Just give it time to react and settle in .
For your first time , bank the coals off to the side with some wood chunks . See how it goes . You can always finish in the oven like said above .