I always do clouds with the "burn" tool. I set the opacity to about 5 or 6, then start at the top of the photo and make dozens of brush strokes, going further down the photo. Then I use the smudge tool to touch things up.
Thanks! I wasn't sure about the red shed, but that's what they wanted. I will say I am proud of the clouds. The sky was all white and overexposed in the original, so I made those fake clouds
I like the way you did this. Very clean and that red shed is very noticeable. Nice work!