"Be regular and orderly in your daily affairs
that you may be violent and original in your work."
The more I read about writers I admire, the more I realize that each has a system. The particulars of the system may differ, but for all, routine and stick-to-it-iveness makes the difference. The trick, perhaps, is in finding the system that works for you.
Stephen King strives to write 10 pages per day whereas Hemingway's goal was 500 words. Churchill and Nabokov wrote standing up at a lectern. Colette and Truman wrote in bed or on a couch, lying down. Trollope aimed to be at his writing desk by 5:30 am and wrote 2500 words before breakfast. His success was to "allow myself no mercy."
Beyond putting the words on the page, a writer must find a way to organize the business of writing. When I began writing for publication slips of paper flew everywhere - ideas, notes, quotes, snippets I'd overheard. I had to find some way to organize my writing life. But organization needed to flow throughout my entire life, not just the writing time.
I run a fairly well-organized household (although it seems to have been more so when I had three children at home) and I needed something that would suit my entire life, not just the writing portion. Julia Hood's The Sidetracked Writer's Planner works for me. It's full of blank forms to personalize - calendars, query index, income and expense records, idea index, addresses, etc. Best of all, I just print the pages I need (it comes as a PDF) and ignore the rest. I've used that system for nearly 8 years now, while writing for publication, while completing my B.A. in French, and now while working on a non-fiction craft book. I like the flexibility.
Find a system that works for you and stick with it.
Note: The OrganizedWriter.com website has not been updated for several years, but I believe the materials are still available.