Place the Hickory wood chips directly on your charcoal on into a smoker box on your gas grill to get a cooked over wood flavor.
When selecting your wood chips the first thing to consider is how strong a smoke flavor do you want? Hickory provides a bolder smoke flavor then fruit woods and is the most popular smoking wood in the US. Some people can find it overwhelming especially when used with lighter foods like fish or chicken. To prevent this mix the wood chips with a fruit wood (we like to use apple).
That is not to say that the flavor will overpower your food if you tread lightly. When experimenting with smoking start with a small amount of hickory and work your way up.
Hickory is not sweet like fruit woods and not as harsh as say a mesquite. It gives off a straight smoke flavor that pairs well with most of the sweeter barbecue sauces on the market today.
While typically recommended for use with most meats when used with pork hickory smoke really shines through. In fact most barbecue joints in the southern states use it.
When grilling with wood chips there is a debate on the need to soak them or not. I for one will soak my chips before and extended cook but not soak them when cooking steaks or burgers.