Delete the images selected inside the rectangular selection.

By this method the images are hidden through Layer Mask. So that they can be edited whenever required during development.

5. Use Airbrush Tool to blend the image edges.

Select Airbrush Tool from the Tool box.

Adjust its brush size by pressing Ctrl + (plus icon) to increase the brush size and Ctrl - (minus icon) to decrease the brush size. Select normal in the options with a flow & opacity of 100%.

6. Move the Airbrush over the sharp edges of the images and blend the image edge with the background.

7. While blending an image at the layer mask level if accidentally a part of the image gets erased then to retrieve that part, change the settings of the color in the tool palette to white (foreground color) & black (background colour).

Move the Airbrush over the image which got erased.

An easy way to handle Layer Masking is to toggle between black & white color in the foreground as well as background, Tool Palette. The shortcut for this action is "X".

8. If the given layer mask effect is not as expected then to retrive the original image, right click on the respective layer showing the area masked.

9. A drop down menu is displayed, click on 'Remove Layer Mask'.

This action is followed by a pop-up window "Apply mask to layer before removing" with the options "Apply, Cancel, Discard".

Select Discard to get the original image back.

10. Masking can also be done by the Eraser Tool.

Select the Eraser Tool, adjust its brush size. Select Airbrush in the Eraser options with pressure of 100% opacity.

11. Start erasing sharp edges of the images, thus blending it in the background.

Toggle between eraser tool & airbrush tool to give a fine look.

12. Another option for Layer Masking is by choosing the "Hide All" option.

Layer > Add Layer Mask > Hide All

This option hides the image, while trying to retrive the part to be displayed.