Working with layers : Organizing layers by color
 
Organizing layers by color
To organize the Layers palette visually, you can specify highlight colors for layers and layer groups. The highlight color appears as the background of the icon to the left of the layer or group name. It has no effect on the image itself.
In a layer group, layers that have not been assigned individual highlight colors inherit the color of the parent layer. You can use the same highlight color for all layers in a layer group and different colors for layers in other layer groups.
To set a highlight color for a layer icon
Edit workspace 
1 On the Layers palette, double-click the layer to open the Layer Properties dialog box.
2 Mark the Highlight in Layers Palette check box.
3 Click the color box next to the check box.
4 Choose a color, and click OK.
5 In the Layer Properties dialog box, click OK.
The icon appears with the highlight color.
To choose a highlight color for recently used colors, right-click the color box, and click a color.