3d art, also known as decoupage, Decoupage is highly prized for its total uniqueness. Several prints of the same picture are painstakingly cut by hand using a knive. Knowing what to cut out and what to throw away is the key to a good decoupage picture, the pieces can then be layered using glue pads,usually just 3 layers, but some can be up to 5 layers. A good way of hiding the pads is to gently smooth the edges with scissors so they turn under slightly.