Perhaps not exactly a tutorial but some show and tell as to how I created this image.
I used three images that I shot over the weekend at various Smithsonian museums.
The shell, a blue rubber string installation and a metal sculpture.
Before I started working on the collage I adjusted the shell image to enhance it's contrast using a Levels Adjustment Layer, repaired the bottom left corner with the Clone Stamp tool and cropped the photo down looking to make sure that darker portion of the image was about 1/3 of the way up - remember that lovely design "rule of thirds"? I then merged the adjustments and flattened it.
The other two images were not changed from "sooc".
With my shell as my Background layer I applied another Curves Adjustment to enhance the contrast even more.
I dragged my blue strings image into my working document as a Smart Object and after cycling through the blending modes decided to set to Overlay, and with an Opacity of 44%.
I did not want the string all over the shell image so I added a Layer Mask and painted away the parts of the string I did not want.
Next came the letter layer which I again brought into the document as a Smart Object and set to the blending mode of Overlay, Opacity 45%.
The letters looked rather stark so I used a Gaussian Blur Filter to soften the image.
I wanted to remove a similar portion of this layer away from the shell so I copied the layer mask from the strings layer and added a layer mask to the letters so that similar portions were hidden.
Finally I added a texture from Pixel Dust Photo Art, and set the blending mode to Hard Light, Opacity 100%.
And there you have it! Quick and easy using three random snaps that weren't particularly fantastic photos as stand alone images but turned into something lovely when combined.