1. Preheat convection oven to 325 degrees (For regular oven, increase heat to 350 or 375). Prepare an empty beer or pop can by washing the outside. Fill the can about 2/3's full with liquid - beer, water, juice. Then I very lightly coat the top half of the side of the can with a little oil -- it helps the chicken slip out easily after cooking. Place the can in the bottom of a broiler pan.
2. Slip the chicken (washed and patted dry) on top of the can pulling the legs forward and apart. Push its little backside firmly down on the can -- you'll know when it is on securely.
3. Paint the chicken lightly with heavy cream or half and half, even whole milk will do. The fat content in any of these will cause the chicken to brown and crisp beautifully. Butter works, but I find it too greasy for me.
4. Choose your herbs or spices and sprinkle and pat them on all over the bird. For this bird, I sprinkled it with onion powder and salt, then McCormick's Louisianna Spice. I use different spices nearly every time I make this and they are all wonderful. Even just salt and pepper is nice.
5. I usually bake a 3 1/2 lb bird for 50 minutes and it is perfect. I baked this 4 1/2 lb gal for 60 minutes then pulled it out to test by cutting away where the leg joins the breast and slicing a small piece of the lower breast. The breast meat was perfect, but the leg still looked a litle pink. I wanted to pop it back in for another 5 or 6 minutes but "the husband" was standing behind me wailing. So I cut off a leg for him and popped it into the microwave for 20 seconds to finish cooking. It was perfect, and the breastmeat was juicy and delicious. He loves the crispy skin.

Oh, be very careful when pulling the chicken off of the can -- remember, it is filled with scalding liquid. I usually have a platter next to the pan, insert a fork through both sides of the chicken, and gently lift and wiggle it off the can.

I did a little slideshow on this. Hope it is helpful.

Here is a link that might be useful: Beer Can Chicken