Haven't done for a chicken but every Thanksgiving (here in the U.S.) we do one turkey brined. Simple, really, one just needs a non-reactive container big enough to cover the bird and the brine as well as a place to keep it cool.
Here's a simple recipe similar to the one we use but sized for a chicken. You can use different spices and herbs to suit your taste and some substitue chicken broth for some of the water:
1/2 cup roasted garlic cloves
2 cups water
1 Tbsp salt
1/2 teaspoon freshly ground black pepper
1 Tbsp olive oil
1/2 lemon, cut into 4 wedges
2 bay leaves
1 (3-4 pound) whole roasting chicken
Method
1 Prepare the brine by combining garlic, water, salt, pepper and olive oil in a blender. Squeeze the juice from the lemon wedges into the brine, blend. Stir in the bay leaves.
2 Place chicken in a large, resealable plastic bag, or in a large non-reactive bowl. Pour the brine all over the chicken in the bag, or in the bowl. Add the (already squeezed) lemon wedges. Squeeze out all the air from the bag and seal, or place plastic wrap over the chicken in the bowl. Refrigerate overnight - 12 to 24 hours.
3 Preheat the oven to 375°F. Remove the chicken from the brine. Sprinkle salt and pepper all over the chicken. Place the chicken on a rack, in a roasting pan, breast side up. Roast for about an hour, until the juices run clear from the thigh when pierced with a fork. (Thigh meat should have an internal temperature of 160°F before removing from oven.)
Let the chicken rest for 10 minutes before carving and serving.