When I was little, I think we bathed once a week, and strip washed on the other days. I can't recall how often changes of underwear happened, just that we were always clean and well dressed. For one thing, my grandmother was a tailor, so a lot of our clothes were 'bespoke'. Of course, I longed for shop bought clothes like everyone else.
Being an army child, I was sent to boarding school aged twelve. Baths were at an appointed time, as we shared the bathrooms with others. No showers in those days.
I remember we were all (whole school) to attend an event where the Queen would be present. On the appointed day, we had to wear only clean clothes, so had to save a clean shirt for that occasion. I was mortified as I really could have done with a change of shirt a day or so beforehand but wasn't allowed to. I felt horrible though.
The prefects who oversaw who was wearing what needn't have worried. On the day, HM was no closer than the other side of a very large parade ground. She wouldn't have known (or smelt!) who was wearing what, and anyway there were hundreds present.
What a palaver!