OK, took me about 20-30 minutes to do but I think i've done not bad for a very first attempt (even if I do say so myself - prepares to get flamed...
)
Did the large areas of sky with a large, hard edged brush and then fine tuned it around the trees. the blurred the edges by reducing the opacity and hardness.
If truth be told I got a bit boarded, so the trees on the rhs got done a bit roughly, but I've not got the patience..:o


