As I’ve been working on my own projects, on my own schedule, at home, I’ve taken to having breaks; sometimes, even short naps.
I don’t really have a fixed schedule. I generally start the day with some goals, and usually take breaks between work on each goal. Sometimes, they are an hour or more. I may do errands. I tend to start the day quite early, and often work until bed.
If I am stymied by a nasty problem, I will often take a break, and maybe watch a part of a movie, or something, then go back to it. Bugs never last more than a day, with me.
If it’s a big context switch, I may have a “take it easy” day, where I take care of administrative crap.
I enjoy more productivity than I have in my entire life.