Bathing may or may not be your highest water use. Gardens/lawns can be very water intensive, pools/dams/tanks due to evaporation, or even hand washing etc

But, as you specifically mentioned bathing:

I do cold showers for maybe 6 months a year centred on summer.

It sure makes you minimise shower time and operate at maximum efficiency at either end of that period. Brrrrrrrrrrrr!

To further minimise water use, use cold water during winter too.

Other things to consider:

• if showering, make sure you have the low flow shower heads
• at least halve your water use by sharing your bathing time/water with other(s) ;)
• depending on the above, a bath may use less water than showering