Up to 60% of the human adult body is made up of water. Each day humans must consume a certain amount of water to survive. Of course, this varies according to age and gender, and also by where someone lives. Generally, an adult male needs about 3 liters per day while an adult female needs about 2.2 liters per day. All of the water a person needs does not have to come from drinking liquids, as some of this water is contained in the food we eat.

Tips:

If you’re thirsty, it’s possible you’re already dehydrated.
Start out by just increasing your water intake in small amounts over time.

Source(s): https://water.usgs.gov/edu/propertyyou.html