I've been working for 5 1/2 hours, and the apartment STILL looks like shit! 
It has to get worse, before it gets better.
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Focus on what has gotten better, even if it is not obvious yet.
My bedroom looks absolutely awful right now. Still working on the books. Have been dusting a lot of them outside the window today, and a few shelves look neat, clean and well filled. For the rest, piles of dusty books everywhere. And the scent of both dust, and cleanliness. Weird mixture. Wonder how much I will be sneezing tomorrow-morning.