Cabeza guateada

So, imagine that you have a really soft and fluffy pillow. You can squish it and it feels really nice. Now, imagine a bird called a guanaco. This bird has feathers on its head that are also really fluffy and soft, like your pillow. But instead of being just one color, the feathers on its head have different shades of brown and gray, kind of like when you mix different colored paint together. When we say "cabeza guateada," we are talking about the guanaco's head feathers and how they look all fluffy and mixed in color, like a squishy pillow.