Years ago, I read an interview with Richard Branson. He said that one of the keys to his success is that he stopped seeing a difference between working and not working. I'm paraphrasing, but he basically said it was just living. He worked. He spent time with his family. He played. He worked some more. It was all just living.
Granted, that may be easier to say when you're a multi-billionaire and family time is spent on a tropical island you own. But still, I think he's given us a key.
The best creatives I've known come to work the next day and say, "Hey, I had this idea last night. What if we..."