Grouping layers in Photoshop involves linking multiple adjacent layers and using the transparency of the bottom layer of the group as a mask for the other layers. This means that the upper layers are visible only through the "window" created by the transparency of the bottom layer. You also can use a layer mask for the bottom layer in the group instead of actually erasing part of that layer (see Task 7, "How to Add a Layer Mask"). When layers are in a group, the thumbnails in the upper layers in the Layers palette are indented and shown with arrows, and the line separating the layers is dashed instead of solid.
Open the File
Choose File, Open and select the image file you want to modify.
Choose Window, Layers to display the Layers palette. Arrange all the layers to be grouped so that they are adjacent; make sure that the layer to serve as the mask is positioned at the bottom of the group. In this example, the Background layer is at the bottom of the stack, a text layer is just above it, a layer with texture is just above that, and the top layer contains lines drawn with the Paintbrush tool.
Link the layers of the group together, following the steps in Task 2 of this part. For this example, select the text layer and then click in the column closest to the layer name to make the chain icon appear.
Make sure that no layers are linked except for those in the target group. Choose Layer, Group Linked. The layers that you linked are now grouped, as you can see by the arrow icons and the way the layer names are indented above the bottom, mask layer.
If you want to ungroup layers in a group, select the layer to be removed from the group in the Layers palette. Choose Layer, Ungroup. This action ungroups this layer as well as any grouped layers residing above it.
Setting Opacity and Mode
Set the opacity and mode by highlighting the base layer of the clipping group (a group in which the bottom layer acts as a mask for the layers above it) and modifying the Mode drop-down list and the Opacity slider at the top of the Layers palette.
You have two methods for adding layers to a group: One is to hold down the Option key (Mac users) or Alt key (Windows users) and position the pointer over the solid line dividing two layers in the Layers palette. Click when the pointer changes to two overlapping circles; the two layers are now grouped. (You can also use this method to ungroup layers.) The other grouping method is to highlight a layer in the Layers palette and choose Layer, Group with Previous to group the highlighted layer with the layer above it.