Using layers

Am using Sketchup 2017. And i want to use layers.When look about this on youtube i see layers directly on the working area.
When i klick on toolbars for layers it not showing it on the working area,but only on the top.
What do i wrong?

Look in Window>Default Tray. Make sure Layers is selected to be included. And make sure the Default Tray is set to be visible.
Screenshot%20-%2010_7_2019%20%2C%209_27_52%20PM

Before you get into using layers make sure you understand their proper usage including leaving Layer 0 active at all times and leaving all geometry with the Layer 0 tag.

Thanks. I gone try it.