In the fall of 1965, while teaching at the Iowa Writers' Workshop, Vonnegut wrote his wife Jane a letter that mapped his day almost to the minute. It's one of the most precise records we have of how a major novelist actually spent his hours.

The Direct Answer
Up at 5:30, writing by 8, a midday swim, asleep by ten.
He laid it all out in a letter to his wife Jane dated September 28, 1965, later collected in Kurt Vonnegut: Letters.

The Hour-by-Hour Day

The morning was the engine of everything. He'd wake at 5:30 and write straight through until 8:00, break for breakfast at home, then write again until 10:00. After that he walked a few blocks into town, ran errands, and headed to the municipal swimming pool, which he had entirely to himself, for a half-hour swim.

He was home by 11:45, read the mail, and ate lunch at noon. The afternoons went to schoolwork, either teaching his students or preparing to. He got back around 5:30, poured a few belts of Scotch and water to quiet his head, cooked supper, read, and listened to jazz before falling asleep at ten.

I awake at 5:30, work until 8:00, eat breakfast at home, work until 10:00, walk a few blocks into town, do errands, go to the nearby municipal swimming pool, which I have all to myself, and swim for half an hour, return home at 11:45, read the mail, eat lunch at noon.

Kurt Vonnegut, letter to Jane Vonnegut, September 28, 1965

Exercise Built Into the Gaps

Vonnegut wasn't a gym person, but movement threaded through his day. The swim broke up the writing block, and in the same letter he mentioned doing pushups and situps regularly, saying he felt he was getting lean and sinewy. For a man who spent most of his life at a desk, the physical stuff was a deliberate counterweight.

For the full picture, including how he wrote and the famous rules he handed down, see the full Kurt Vonnegut writing routine.

What You Can Steal