All of these leaf pictures were taken from one Brachychiton Acerifolius (Illawara Flame tree) on the same day. As you can see these trees have a significant amount of variation from one leaf to another even on the same tree. I have seen leafs with just one lobe to leaves with up to nine lobes although typically they have three, five or seven lobes.
The leaves in these pictures are about 6-8 inches long and have a smooth texture.
It is also very common for leaves to be irregular in shape with the lobe on one side being more fully formed than the opposite lobe on the other side.
Ten Thousand Trees