A mannequin head used as part of a storefront display should be painted to complement the aims and ambiance of the store. If the store is an upscale fashion boutique, a mannequin head painted in the style of the '40s or '50s makes a clever foil for the latest hats and hair accessories. If the focus is strictly on the object the mannequin displays -- such as glasses, wigs or jewelry -- the mannequin head may be only lightly painted. If the store sells ultramodern products, or is aiming for a slick vibe, the mannequin head may be shiny, painted one color, or not painted at all.
If you're using the mannequin head as part of an art project, you can do anything: mannequin heads have been covered with bright latex paint, plastered with stickers or papier-mache, painted with flowers and cracked open with hammers in the name of art. Consider the statement you want to make, and which effect will communicate it best. Will the mannequin head be a dry comment about vanity, an apocalyptic warning against technology run amok, or merely an inkblot meant to be interpreted differently by each viewer?
A mannequin head can be painted and used as a teaching tool to show students the different areas of the brain, the location of facial nerves or the shape of the skull. Several of them together might be used to demonstrate the distinctive face paint or tattoos of different aboriginal tribes, Japanese Kabuki face painting or ancient Egyptian eye makeup.
A mannequin head can be a lot of fun for a group of little girls, as toymakers have discovered. Turning them loose with a mannequin head, an old wig and a box full of makeup may mean you need no other entertainment for a princess party, or even a sleepover. If you give it to boys to paint, you'll probably end up with a nice window decoration for Halloween.