Colors: Magenta, White, Lime Green, Teal
Milan and Cuba are very close, Cuba just has that stronger punch of teal in it.
Load a 1″ flat brush (or smaller width brush to pick up fewer colors) back and forth over the cake, using a small amount of water to moisten your paint.
You can either spray the cake or use a wet brush to moisten the paint.
Re-load making sure brush is lined up again with the correct colors. Hold the cake vertically so that any dripping paint will run down the color of the stripe, and not across the whole rainbow. When making strokes try not to twist the brush so that the colors overlap.
Rinse and repeat if colors start to get muddy. Note that fewer colors in your cake will often lead to cleaner strokes.
You can also use these cakes with face painting sponges to do base work or with and dauber sponges to make rainbow spheres that can morph into all sorts of cool things!