MerylStreep
I don’t waste any water, and I mean any
So it’s in shower, wet hair, water off, shampoo. Wet flannel, wash all over, rinse off.
I reckon I’m well within 1 min for whole shower and shampoo.
If I did that, I would waste more water waiting for my combi boiler to fire up again and get hot water through to the shower - furthest room from the boiler so I have to run it for several minutes before it is warm enough!
I have to do the same in the kitchen although in the summer I save some of the cold or tepid water to use on my patio pats. I tend to wash my hands in cold water rather than wait for the hot water to run through.