STEP 3
Now select the sky.
Now you may thinking that it is a perfect selection but believe me, it’s not. To further refine the selection click on refine edge in the option panel. In the refine edge box, turn on smart radius and then increase the radius to 250 pixels. Increase the smooth to 100 and increase the shift edge to +16%. Press OK.
I have written a whole tutorial on Refine Edge tool which might be helpful to you.
