I have a Char-broil gasser and a Old Country BBQ lump/stick burner. When I use the gasser, I have a cast iron skillet on a grate where the combo chip pan/water pan used to be. I also have a water pan on a rack above that.
I will get my smoker up to the temp I want to cook at, then I'll put in a chunk or two of whatever wood I'm using. You don't need to soak chunks, the water will only penetrate them very little and it's evaporated almost immediately once they hit the iron skillet. I'll adjust my temperature as they start to get going, and let them start producing that thin blue smoke, and then put my chunk of animal or fowl in the smoker.
Mine has a separate door for the burner so I don't lose much temp adding a chunk as it's needed when the smoke starts to dwindle. As you cook more, you'll learn the ins and outs of your smoker, and when to add chunks.