To create a Switch layer, simply click the New Layer button in the Layers palette and choose the Switch option from the pop-up menu. The new Switch layer is created directly above the current selected layer and is named Layer followed by a consecutive number.
The Switch layer icon is a folder with a small black diagonal arrow on it, as shown in Figure 24.1. Switch folders can hold multiple sublayers. To add a layer or multiple selected layers to the Switch layer, simply drag-and-drop the layer or layers onto the Switch layer in the Layers palette. The Switch layer will be highlighted red when the dragged layer or layers can be dropped.