Art is signed by taking your non-dominant hand flat in front of you, with the palm facing your body as if it were a canvas. Take your pinkie finger from your dominant hand outstretched, and scribble with it on your non-dominant hand as if you were drawing.
Art is generally used expansively to describe drawing, painting, and generally any type of craft. Use the sign before you start any art time. Your baby will quickly catch on, and then she will be able to let you know when she wants to do art. You can also use the sign to show completed artworks done by others, so your baby can start to make the connection between doing art and the end-product art.
Art is best achieved as your little one begins to discover how they can express themselves by creating simple art pieces or crafts. It is also useful when showing your baby art or crafts made by others.