Typically, a battleship's crew would be larger than required for the day-to-day running of the ship, but this was down to the watch system. As the ship needed to be manned 24/7, the crew was divided into parts. This allowed the ship to stay manned while men rested. Battleships usually used a two-watch system, with the crew divided into two parts, 'port' and 'starboard'. Each watch would have four hours on duty and four hours off to rest and relax. The one exception was the two dog watches, which were two hours long. The dog watches meant that men did not have to stand watch at the same time each day. The engine room crew were on a three-watch system, which allowed each watch to get an unbroken eight hours of rest a day. When a ship was in port, only a quarter of the crew needed to be on duty at any one time, so each of the two watches were further divided into two parts. There were also a number of 'daymen', who only needed to be on duty in daytime and as such were not divided into watches. These were those working in incidental roles, like stewards, clerks and the medical staff.

When a watch was on duty, there was plenty of stuff that needed doing. Cleaning and maintenance were constant companions. Those on watch would spend time cleaning and maintaining parts of the ship. The paintwork is particular needed constant work to ensure that it was always up to a high standard. Other duties included cleaning the 'heads' (ship's toilets), maintaining the magazines, and sweeping the decks. In the Arctic, men would spend much of their time chipping ice. Beyond cleaning and maintenance, men were also needed as lookouts, helmsmen and other such duties. A man would typically spend an hour of their watch on one of these duties, before going on to more strenuous duties. If there was a risk of action, then a portion of the armament was manned. How much of the armament was manned depended on how close the threat was. In the Mediterranean during WWII, it was not uncommon for the turret crews to sleep in their turrets. There were four states of readiness for both AA and anti-ship operations (LA). In the fourth state, only a quarter of the AA battery and one LA turret were manned. In the third state, known as defence stations, half the guns in the ship were manned. In the second degree, all of the guns were manned, but the men were allowed to rest, and groups of men were fallen out in turn. In the first degree, all men were at their quarters. If there was a risk of air attack, a strong watch was kept for enemy aircraft.

When the men were off duty, a variety of recreations were available to them. On the messdecks, men would often play games; the Royal Navy's unofficial boardgame was 'Uckers', a form of Ludo. Darts, bridge, cribbage, and whist were also frequently played. Gambling was prohibited, but a number of illicit games were often played. The game of Crown and Anchor was particularly common. For those who wanted to listen to the radio, then it was possible. Ships would play recorded music and radio programmes over the tannoy system. This was very popular, and allowed men to keep up with current events as well as listen to popular records. Another frequent diversion on the messdecks was crafting. Leatherworking, ropework and tapestry were all commonly done, especially by the older seamen, and there were frequent competitions. These also provided an avenue for a seaman to earn extra money by selling pieces to his shipmates and officers. For those who wished to work together with their fellow seamen, clubs and societies were often encouraged. Dramatical and musical societies were particularly popular, with concerts and theatrical productions being a highlight of many dull voyages. Ships also carried a library. Hood, for example, was issued with 700 books by the Admiralty, which could be borrowed freely by any member of the crew. One of her officers in the interwar period established a subscription library using funds from the ships' canteen committee. Borrowing a book from this cost a penny a week, but it had a much wider selection of titles (with some 5,000 books in it) and they were more fitting to the tastes of the average seaman. She also had a bookstall, selling books, useful items and souvenirs. Ships would also carry a cinema projector, which they would use to show films two or three times a week.