Kartiks if you wantg to do a Water Fast you have to start on fruits, before we fast for ramadan we do a week on fruits like oranges grapes magos, basically fruits high in water, this will get your stomache used to taking light food and high water.
then after a week it should be easier and safer to start the water fast.
lol but its HARD!!!!
Im fasting 16 hours a day at the moment with no water either and its kind of hot weather..im dying.