Inspiration can show up almost any time, though I have yet to see anyone scratching out melodic ideas on a restaurant napkin as legend would have us believe. I think inspiration comes from concentration, and early on I learned about Mark Twain's habit of leaving for his study after breakfast and not reappearing until the end of the day, ready to read to his family what he had just written. That set a good example for me, although I didn't copy his habit of taking twelve cigars along.