APPLYING ALPHA CHANNEL :- - photoshop tutorial

1. Open an image. (Open two images separately).
2. Now "CTRL+A" to select one image and "CTRL+C" (copy it) and close it.
3. Click on the second image and goto Window>channel. In channel palette, Add a new layer i.e. Alpha channel.
4. Paste the two image in the new alpha channel. Adjust the pasted image position and click on RGB channel.
5. After this click on layer palette and select the image layer and goto Filter>Render>Lightening effect. Settings as:
    Lightning style:    0 clock
    Texture channel:    Alpha and Click OK