Creating layers
To create a layer, click the New Layer button 
in the Layers palette. The new layer is added to the Layers palette, in front of the active layer. The new layer is active by default, which means that any items you create will be placed on that layer.
To create a new item on a particular layer, first click the layer’s name in the Layers palette to activate that layer. Then use any of the standard item creation tools to create items on the layer.
Parent topic: Working with layers