The plaque at the former Nicholson's Cafe in Edinburgh, Scotland, where, in 1993,  J. K. Rowling wrote much of her first novel, Harry Potter and the Philosopher's Stone, in longhand on paper tablets. If you're going to make 2020 your best writing year ever, first there's something you'll have to do. You'll have to overcome all those excuses you come up with every year to explain why you're not writing. Every writer knows the drill. You've got the perfect writing day planned—snack stash full, hubby on a weekend fishing trip with his Dad and brother, children on an overnight playdate with their cousins. You're going to make that deadline, or you're going to start your novel or at least get a couple of thousand words written. You're going to make forward progress. And then the cat throws up on your grandmother's Oriental rug, the kid across the street hits a home run that comes sailing through one of your windows, a closed window of...