Photoshop: Layer Masks

The window was plan with no tile and window view was palm trees.I place the tile image over the window layer. I then made the layer somewhat opaque so i could see the window underneath. I used the Pen tool and click all around the window to make a selection and made it to a black mask. I used the same techniques to place the city in the window view. I last thing I did was the text using the text tool.