If the wall is not flat, then you can use plywood, plywood strips, wooden keel made of substrate mounting.The thickness of the plywood is generally chosen based on the size of the installation area is calculated.Plywood market generally with 5 cm, 9 cm, 12 cm, etc. The greater area selected thicker plywood,general recommendations with more than 9 cm.First plywood installed,then amount the mounting position of the decorative panel,the ecological wood on the wall,then the public opening position obliquely nail fixation,usually once every other 30 cm hit the nail,after installing a plug and then the other one go,In the same manner until the installation is complete.