This is easy - and tastes magnificent.
Start by making a stuffing mix. Take, say, 4 slices of bread and grate to tiny crumbs. Add about two large lumps of butter. Add one oniion, chopped finely. Sprinkle a generous amount of dried sage (from any supermarket) on the mix, and get your hands in there and mix really well. That goes inside the chicken before you put in the oven (I know that sounds obvious but some people will ask...!)
Next, seperate the skin from the meat on the breasts, without fully removing it (you can easily get your hand between them, trust me). A knob of butter on each breast but under the skin will keep the bird basted.
Nearly there.
Now, you can put a couple of rashers of smoked bacon on the top and put the whole thing in a casserole dish/oven brick/covered roasting dish, and into a pre-heated oven, gas mark 4�, for 90 mins. Allow to stand for ten minutes before carving, serve hot. Delicious!