I’m reading Virginia Woolf’s To the Lighthouse and came across this passage that very clearly describes the struggle of making the piece of art you have in mind:

She could see it all so clearly, so commandingly, when she looked: it was when she took her brush in hand that the whole thing changed. It was in that moment’s flight between the picture and her canvas that the demons set on her who often brought her to the verge of tears and made this passage from conception to work as dreadful as any down a dark passage for a child. Such she often felt herself—struggling against terrific odds to maintain her courage; to say: “But this is what I see; this is what I see,” and so to clasp some miserable remnant of her vision to her breast, which a thousand forces did their best to pluck from her.

Is this not a very common experience? The passage from conception to work can be quite a breach to cross sometimes. There are times when you don’t really want to do the work, and so that demon of sloth or what have you darkens the passage. There are times when you are all about doing the work, but the picture isn’t clear enough when you grab your construction tools, or you feel like you lack the skills to take on the task you’ve set out to accomplish. Those demons come in many forms, but discipline guides one to their goal; though you might not get to exactly where you had in mind or in the way you originally planned. Still, the key is to go at it, one goal after another and watch yourself grow stronger, as you advance in knowledge and confidence.