I just created this image.
What it takes is only your imagination (..and bit of the photo editing skill.)
Because when I saw this image,
I thought "hey, it's only vertical flipping; I can do that too."
So, I took the Jodoga-Hama beach picture from this page to create the similar image.
I cut the Jodoga-Hama beach horizontally at where I want make the reflection in the bottom of it. Also, I made the lower half bigger by cutting little bit off from the upper part to emphasize the reflection just like the image above. (I have just noticed what this person who created the image on above was "stretching" the reflection part longer vertically, not cutting a bit. O, well.)
Then, I got the keyboard girl from this site.
I place her front middle part of the image to make it looks like she is creating her background world by playing her keyboard. Then, I flipped her and shorten it to make the reflection. (How come I did not notice this method when I was working on the background? O, well.)
What it takes is only your imagination (..and bit of the photo editing skill.)