I've been reading a good book called "Making Things Happen" (Scott Belsky). The key point of the book is that everything relies on action. Belsky's Action Method is geared toward making things happen in companies, but the same basic ideas apply to individuals--for instance, to getting your project written. Here are three of his tips and how they could help writers:
1. "Hire the Killjoys." It's likely you have too many ideas and want to implement all of them at the same time, especially since starting a new project usually is more fun than working on an existing one. You need to have the killjoy part of yourself set and stick to priorities. You can do all your projects, but not all at the same time.
2. "Work with a bias toward action." Don't wait for the right time. It's never the right time. Otherwise you'll go through life saying, "I'll do it when...the kids are older...the kids have left home...when I retire..." And one day it'll be too late. Start now, even if you can spare only a few minutes a day.
3. "Change your vocabulary." As well as talking about your big dream, talk about the exact things you are going to do today, tomorrow, and this week, even if you are talking only to yourself.
(for a total strategy for getting more done, get my book, "Focus: use the power of targeted thinking to get more done" from Amazon or your other favorite online or offline bookseller.)