Découpage is a type of collage, and can refer to either the artwork itself or the technique used to create it. The technique consists of applying a découpage medium such as Mod Podge to the item, pressing the papers into place, and applying another coat of medium. Découpage can be used in conjunction with paint on canvas to create mixed-media art. In addition, the technique can be used on almost any surface and with almost any type of two-dimensional paper.
Arrange the napkins on the canvas until you are happy with the design.
Remove the napkins a few at a time and apply découpage medium to the canvas with a sponge brush. The medium should completely cover the canvas, but not be excessively thick.
Press the napkins into place slowly, eliminating any air bubbles or wrinkles immediately.
Continue until all napkins have been pressed into place. Allow to dry for at least 30 to 45 minutes.
Apply a thin coat of découpage medium on top of the collage of napkins using a light touch with a soft sponge brush. Allow to dry for at least a half hour and add another thin coat.
You may want to coat the finished project with two to three layers of acrylic spray varnish or clear coat for a glossy finish.