Here's a radical idea. Have only one project at a time. (On the website of my former colleague I notice there are about 5 projects s/h/e has been doing in the last five to ten years, with zero books published.) Work on that project all the time. ( Don't wait for a block of two or three hours or the perfect atmospheric conditions.) Don't work on anything else substantial until you have finished that one thing. Right now, for me, it's my MLA talk. If I work on it a little today, a little tomorrow, and so on I can finish it by a week from today. Then I can do my syllabi for next semester, then my talk on Ullán for Madrid in January, and finally my critical edition. January all I will have to do is teach my courses and go to Madrid. After that I will write my book Lorca and Modernity, taking on absolutely no other projects, even book reviews.