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We're all rushed off our feet, running around all day, so how can we catch time? Like sand it slips between our fingers, gets stuck to wet feet, ruins picnics, stays in the boot of the car for months...
Sorry I'm getting a little carried away there. The answer is to start building your castle. As I read somewhere a while ago, yes we moan about not having enough time, but we've got about seventy years, how much more do you need for heaven's sake?
Even assuming you're getting on a bit, you've probably got a few years left.
So, what was it you wanted to do? Learn the piano? - I'm sure 15 years should be plenty, speak a foreign language? get started, sleep more? go to bed.
Whatever is was, start it and the rest will take care of itself.
Oh, and don't forget those castles in the sky, they're trickling away too.