Hi! i have a client who owns a nail salon and would like a classy nail polish cake. I was thinking of doing something like this, but im not entirely sure how to do the "polish" splatters. Maybe a thinned royal icing poured down the side? Does anybody have any suggestions? 

I've never done one of these cakes, but maybe melted coloured chocolate would work, like Merkens.

Athis is gorgeous!!

Chocolate might work, but would give a waxy appearance when dry and might crack if the cake is flexed.  I would try thinning some royal icing.

Amaybe some liquid food coloring?

I'd definitely go for royal icing!