In an article in The Times (for which I haven't been able to find a link), Sue Fox told of her interview with Norman Mailer toward the end of his life. He told her this about writing:
"It's very bad to write a novel by act of will. I can do a book of nonfiction work that way--just sign the contract and do the book because, provided the topic has some meaning for me, I know I can do it. But a novel is different. A novel is more like falling in love. You don't say, 'I'm going to fall in love next Tuesday, I'm going to begin my novel.' The novel has to come to you. It has to feel just like love."
The article revealed that Mailer kept up his work habits almost to the end. His son, John Buffalo Mailer, said, "At 84, he still had his work ethic like very few people--treating his writing like a regular 9 to 5 job. You check in every day and go to work."
He also said, "One of the best pieces of advice Pop gave me about writing is to learn how to say something once. Most young writers say the same things different ways. You have to choose the best."
(Not sure how to get started writing your book? Check out "Your Writing Coach," published by Nicholas Brealey and available from Amazon and other online and offline retailers--also see the website at www.yourwritingcoach.com)