For those who are annoyed with a shower that gives you no option for how much water comes out of it (only hot to cold), you can buy these toggle switches. I got one along with a low flow shower head once, but I'm really not sure who carries them alone.
You can control the water flow with them; from full to a bare trickle. I usually turn it almost off when I'm shampooing and soaping and put it back on full when I'm rinsing off. It probably takes a 7.5 gallon shower down to 3 gallons or less! I'm still fully clean, spent the same time in the shower, but I used so much less water and helped the environment, too! Buwaaa!
By thintieguy from Los Angeles
This page contains the following solutions.
Have you ever not had hot water one morning and wanted to take a shower? All you need to do is heat up a 1/2 gallon of water in a good sized pot or tea kettle.
If you have a shower and only one tap, you know you get cold water or boiling hot before getting the right temperature. All you have to do is mark the tap with a marker or whiteout once you find the right setting you like.
When I shower, I turn off the water while I lather up, shampoo my hair, or shave my legs. I'm amazed at the amount of water I save by only having the water on twice instead of running it the entire shower.