Mastering Decoupage is the art of decorating surfaces by adhering paper cutouts, such as images, patterns, or designs, to objects like furniture, boxes, or trays. The process involves layering these cutouts with glue and sealing them with varnish to create a smooth, durable finish. By mastering decoupage techniques, artists can transform everyday items into beautiful, personalized pieces, combining creativity and craftsmanship for a unique, handcrafted look.