Cut out with Poligonal Lasso Tool the part the you need.
step 2 of 5
Deleted the unwanted edges with Eraser tool
step 3 of 5
Created a ground with Clone Stamp Tool.
step 4 of 5
Started to copy the balls and size them. I had to be careful that every layer to be in the right position.
step 5 of 5
this is the final representation of the balls. In the final work you will see a focused image. To do that you need to create a JPG after that open it in Photoshop duplicate it and using the Lens Blur filter you blur it. After that you delete the middle with Eraser tool, with a smooth brush.
Hope you like it ;)
Thanks