Touring for me is a test of endurance. I keep myself fit, eat well, sleep, and rest my voice when possible. It's not very rock 'n roll, but touring when you're sick is pretty miserable, so I try to avoid that.
I view my songwriting like an athlete views his or her sport. I have to practice. I have to stay in shape. So I do it every day. I can stack the odds in my favor by starting with a distraction-free space. I need to feel quiet and relaxed and able to channel things that are deeper than the inputs from my immediate surroundings. I don't want the phone to ring, or the TV buzzing away in the background. When inspiration hits I need to be able to receive it clearly. If I don't catch it, someone else will.