Drizzle them with little olive oil and make sure it's spread on the tops of the garlic.
Close up the foil around them and put them in the oven at 400 degrees for about 30-40 minutes or until soft.
I use Roasted Garlic a LOT. When I make it, I make enough to freeze in small quantities so I can just pull one out of the freezer when I need it. It freezes very well and will add just that touch of extra flavor to so many things.