According to the invention, the surface of a blank to be shaped into a product is decorated by marking on a test blank a plurality of reference points distributed over the entire surface of the test blank which will be affected by the shaping. The test blank is then shaped into a test product and the positions of the reference points are determined. A block of decoration to be obtained on the product is formed, and the positions of the reference points on the test product are located on the block. The decoration is then converted into a plurality of pixels of each inking color, and the position of each pixel with respect to the reference points on the test product is located. A corresponding pixel position with respect to the reference points on the test blank is also determined, and a film is prepared by printing the film with each pixel of the decoration reproduced in a location corresponding to the corresponding location on the test blank. At least one blank is then decorated with the film.