Well done.
But you're a bit lucky with such a sky 
Thierry
Thank you very much Thierry, glad you enjoyed it!

Another beauty.
(But he brings a large set of glorious skies with him in a bag with his Firecrest Ultra Filters.) 
Thank you very much Eric!

As Arnold Palmer* is reported to have observed, "the more I practise, the luckier I get".
Jeremy
* or Gary Player, or [insert name of golfer here].
Indeed

Well, there are two things that really help making my skies look like I am bringing them with me in my bag
1. Preparation. Going to a place in the best season for it definitely increases your chances, and I explore my destinations repeatedly and in different seasons to find the best time to go, both for my own work and for my Workshops;
2. Good, merciless editing (or a merciless editor, if you can find one), both in the field and back home during post-processing. I simply try not to shoot photos that I know I will trash, and when I process my photos after a trip I simply try to process only the really good ones. Finally, I try to post online only the best ones. Not having much time definitely helps, I have a serious backlog and I am almost ready to hit the road again for three months, so I need to loose as little time as possible when editing - which, in turn, means editing only what I think are the very best.
Luck helps, of course, but if you just rely on luck to do this job (or any job, for that matter), you'll have serious troubles in paying your bills, I am afraid

Best regards,
Vieri