Weekdays - Shower every morning before going to work or, if commuting by bike, shower when I get to work.
Weekends - If I'm going out on the bike, then post-ride soak in the bath with plenty of bubbles and music on the bluetooth speaker and sometimes a can of lager. If not going out on bike, then shower in the morning.
Camping trips - Err, what's water? I once got the train back from the Lake District to London following an extended camping trip and, despite the train being busy, soon found myself to have a table and four seats all to myself for most of the journey
.