Your owner's manual should give you a start as to the proper setup. You should start with that and experiment with the amount and flavor of the wood added when it becomes second nature to you. If you no longer have the manual, check with their website for instructions. Some tips on smoking- be careful, too much smoke can overpower the meal. Generally, if the item is large and needs to be cooked over a long period of time, use a bit of heavy smoke in the beginning, then taper off to just a little for the long haul. If you are direct grilling you can pour it on if the item will only be on the grill for a short time i.e. 20 to 25 minutes. Also, it depends on the product, steaks are complimented by the powerful flavor of hickory, oak and mesquite; while items such as poultry and fish may be better off with a light usage of apple, alder, or cedar (loook at plank cooking for an exciting and impresive way to do filets) . (mesquite is also popular with poultry, be careful on the amount used especially if you are cooking a whole chicken or turkey for 1 or more hours). Also, soak the wood chips for an hour or more before use so they generate smoke and not just burst into flame. FYI consider brisket to be a big sponge- little or no smoke is used by the pros when cooking brisket, it absorbes all of the smoke flavor and is easily overdone. They usually just rely on the smokey characteristics of the charcoal to impart the desired flavor. Hope this helps.
Chris