Hi and thanks for asking. It's approximately 15 inches long x 8 1/2 inches wide. There are no instructions for decorating. However, there are lines and emblems inside the pan and outside that you can look at after the cake comes out. There may even be some of them bake into the cake to give you an idea of where to use your talents. Looking at the front of the cake pan also helps. It's not hard at all because it's not that big.