I did one this past summer (if the file doesn't work, just look in my gallery).
I used the Wilton Soccer Ball pan (but any ball pan would work I'm sure), and 2-8" rounds. One of the 8" rounds was used underneath the soccer ball for added height, and the other round was used to carve 2 "breasts".
All of the decorations were made of fondant- I used kelly green, copper (skintone), and black. I iced and covered each "breast" seprately w/ the copper fondant and then positioned them w/ the big iced "belly". Then I draped the green fondant over the whole thing, and just let the bottom part fall naturally (I tried to roll the fondant as round on the bottom as possible to have a skirt-like shape). After trimming the sides and the neckline, I added the black trim and bow.
The cake served approx. 25 people.
If you have any other questions, don't hesitate to ask!!