To me, it looks like it would be done with piping. Make some icing in three or four different colors. You could make the vertical lines around the side of the cake and then go back and make the dots and "hourglasses." Or you could pipe the vertical lines and then put on the shapes with quins.
are you a piper? It looks like you could do those down the side of the cake either with piping or with an extruder, depending on your preference. This isn't a good example of exactly what I mean, but the first that comes to mind, and I can't find the examples I have seen before:
Yes, pipping is what came to my mind as well. The bride requested fondant, so I plan on covering in the pale pink, then pipping the pattern. The cake is going to be two tiered, so I am not sure how to switch up the bottom (or top) tier -- or if I should do the pattern flowing from the top to bottom tier, gradually dying. Any ideas on what to top it with? I was thinking either some color cordinated flowers, or a bow. Also, any idea for a border? I can't picture vertical pipped lines with a horizontal border around each tier. Maybe I am over thinking...?
I vote for piping! Should be a piece of cake!