A clipping mask is created in Photoshop when you use the content of one layer to mask the layers above it. You are basically clipping around the artwork to fit to the shape of the object on the layer. In this tutorial, we’re going to use some text as a clipping mask and the image from another layer will appear through those letters. This is a popular effect both on the web and in graphic design.
1. In Photoshop, open up an image that you want to use. I’m using a snowy scene.
2. Select the Horizontal Type Tool and choose the font properties you want on the tool options bar. Below you can see the options I chose.If we look in the Layers panel, we see the new type layer that’s been placed above the other two layers. Photoshop places new Type layers directly above whatever layer was previously active which is why I first clicked on Layer 1 to select it before adding the text.(http://www.photoshopessentials.com/basics/clipping-masks-and-type/)
3. Click on the document window and type the word Snowfall.
4. Click on the background layer in the Layers Palette to select it and then click on the Create A New Layer button.
5. Using the Paint Bucket tool, fill the new layer with white.
6. Double-click anywhere on the background layer to open up the New Layer dialog box. Rename the layer as Trees and click OK.This places the Free Transform box and handles (little squares) around the type. To resize the type, I’ll simply click and drag the corner handles outward to make the text as large as I need it. I’ll also hold down my shift key as I’m dragging the handles to keep the original shape of the letters intact as I’m resizing them. When you’re done, press enter to accept the transformation and exit out of the Free Transform command:(http://www.photoshopessentials.com/basics/clipping-masks-and-type/)
7. Click on the Trees layer in the Layers Palette and drag it to the top of the layers so that Trees are hiding the words Snowfall.To move the Type layer, I’ll click on it in the Layers panel and with my mouse button held down, I’ll begin dragging the layer downward until I see a horizontal highlight bar appear between Layer 1 and the Background layer:
8. Click on the Layers Palette menu (the little triangle in the upper right corner) and choose Create Clipping Mask, if we look in the document window, we see that the image on Layer 1 now appears to be inside the text! It’s not really inside the text. It only looks that way because any part of the image that is not sitting directly above the type is being hidden from view thanks to the clipping mask:(http://www.photoshopessentials.com/basics/clipping-masks-and-type/)