You all were such a help when I was making my daughter's wedding cake. I want to make this Starbucks cake:

http://www.cakecentral.com/gallery/i/1626570/starbucks-birthday

How do I make sure it doesn't fall over? Is it an 8", 9", 10" and then half a ball on the top? 

Also, how do I make the frosting look like that on the top? The ribbon tip?

Thank you so much for any help!

You can add a center dowel.  The top you can use a tip that will give you ruffle look.

A star tip would work for the top because that's what Starbucks uses to squirt the whipped cream on the drink :)

The cakes are a 6, 5, 4, according to the text below the picture.

Robert