Here's a simple and effective suggestion to save water for those who have showers with separate warm and cold faucets installed from which you make your comfortable showering mix.
Interrupting your shower every time you shampoo or soap inevitably requires adjusting the temperature again from scratch, with unused water going down the drain during
the process.
It is easier but equally wasteful to just keep your water mix running and hurry up soaping. Here’s the trick to avoid both the fiddling and the waste: install a small valve with a simple open/close handle between the shower hose and the shower head.
For interrupting your shower temporally while keeping the mix ideal, just close the valve.
The valves sell at around R40 at hardware stores (don’t forget to pick up an extra washer), are installed in a minute, and even look good.
Since we catch our showering water for later use in the garden, we know that this simple device has reduced our consumption of showering water by about 50%.