A method which may be used for forming an optical effect coating for a light transmission element configured to form a part of a cover of a device is disclosed. The method comprises: printing a first coating layer having a plurality of adjacent first elongated micro openings extending in a first direction in an aperture area, and printing a second coating layer having a plurality of adjacent second elongated micro openings extending in a second direction, the second direction differing from the first direction, in the aperture area. Thereby, an optical effect coating is formed, comprising micro holes formed at intersections of the first and the second elongated micro openings, the micro holes producing locally increased effective light transmittance through the optical effect coating in the aperture area.