ALWAYS ALWAYS ! SAVE A COPPY OF YOUR STOCK AND RENDER BE FORE MAKING CHANGES TO IT. INCASE YOU DON'T LIKE THE CHANGES UMADE AND NOW STUCK WITH IT .

Edit free transform hold down shift that way you won't distort your stock or render used in your tags and to blend in the render, I like to make duplicate layers at times and smudge in a couple of the layers also set to different settings like overlay, screen ,hue, exedra, but only smudge in some parts of it not all ,
GL M8