Brief Answer:
Detailed history required

Detailed Answer:
Hi,
I understand your concern and will try and help you in best possible way,

To help in better way,
I would like to know some more history,
What is height??
Weight??
Do you have diabetes??
High blood pressure??
Do you get frequent urination??
Have you checked your hb(haemoglobin) levels recently??
Any other disease??

To keep youself hydrated you should drink atleast 2-3 ltr of water per day,i.e atleast 12-15 glasses of water per day,
Include dates and bannans in diet they are rich in electrolyte,
Often drink fruit juices,pure fruit juice also hydrates you.
Coconut water is also good source of electrolyte.

See normaly body gets hydrated by this simple measures but due to some problems like vomiting,diarrhoea body looses plenty of fluid for that oral rehydration solution must be taken,

Hope this information helps,

Wish you good health

---