Simple but very pretty. Pipe large bands of colored buttercream icing. THen use an icing scraper to pull and blend the different colors around the cake. This multi-colored smear creates a beautiful, natural look that's unique every time.
Half up⬆▫Half Down⬇▫ The best way for me to get it right on my own hair is tons of dry shampoo for a nice gritty, dry texture at the roots and fine backbrushing with a boar hair bristle brush before tying it up.