By layering, we mean that items should be placed not only in one line. You are free to put them in front of each other. Layering will help you add dimension to your space. How to do it? You should visually divide the space that you need to decorate in three layers. The background layer should be tall. For example this can be an artwork leaned onto the wall. Medium layer should contain medium sized items. And the front layer should have the smallest items that you plan to use. These are the basic rules, but it is up to you to play and find the best combo.