Want to see how to do it?
All you need is a pastry bag and a 1M decorating tip.
Hold your bag at a 90 degree angle. Lightly squeeze and, starting from the middle, work your way around. I think I took it about 1 1/2 turns before pulling away gently.
I didn't make mine as fancy as "i am baker" but I think the roses are adorable. This obviously wasn't a super fancy got-to-be-perfect cake anyway, just something for fun.
Oh, and it did taste delicious. Vanilla cake, raspberry preserves filling, and buttercream frosting. Mmmm.