Key is the secondary use of water
The most important point in saving water is on secondary use of water. The amount of water consumed really varies depending on if you take advantage of secondary use of water.
The easiest one is bath. Generally a single bath tab requires 200 litters of water to fill. If you dispose it after usage, you result in wasting a lot of water.
This water can be used for laundry, cleaning your room, washing your car, etc.
The next part to look at is water in kitchen, such as water used to wash rice, water to cook noodles, and water to wash vegetables. If you could use this water to do dishes, you can save a lot of water.
It is also helpful to use rainwater.