The key to crisping the skin in a roast chicken is to make sure the oven is hot before you put the chicken in. Brine your chicken in kosher salt and sugar first. Once brined, dry your chicken inside and out.
Pre heat your oven to 400 hundred degrees. Slice a clove of garlic very thin and gently separate skin from meat. Slice garlic and place beneath the skin. Brush the chicken with olive oil or melted butter. Season the inside of the chickenwith salt and pepper and place an onion and slice a lemon in half and place inside.
Next, Salt and pepper the chicken and sprinkle with additional herbs if desired. Place the chicken in the oven and let it roast for 5 minutes at 400, then turn the heat down to 350 degrees and roast until done.
If it looks like the breast is getting too brown before the chicken is done, place a piece of aluminum foil over the breast until chicken is done.
If you don't know if your oven is calibrating properly, get an oven thermometer and check it.. When I checked mine, it was actually 50 degrees hotter than I thought it was. So, check your oven.