Hydration is not just necessary for your general well-being. It is also a process that helps your body recover from illnesses, flushing out toxins and maintaining important functions, especially since about 70% of our body is made up of water.
How much water do you need to drink? Drink till you are not thirsty. When the weather is hot & dry, drink beyond your point of thirst (because de-hydration happens when you are not aware). When you are speaking frequently or very busy, drink regularly. This will keep you healthy and well.