Pretty much the same as the normal reccomended daily intake, 6-8glasses of water, and at any temperature that you prefer. Tap water is perfectly ok, but lukewarm is easier on cold days, or if you have a tickly or sore throat, as it is less likely to go down the wrong way and make you cough. Some people like fairly hot water to sip on, especially in winter as it warms you from the inside out. And remember it needen't be all water, fruit juice, and other clear fluids are a good source of liquid intake. My GP goes so far as to tell me I can drink milk, milo, tea etc and they can be considered liquid servings. Having said this, I'm sort of in the opposite boat as I am on a very high protein diet in order to put weight on as I lost heaps and am under 40kgs at present. (not as bad as it sounds!)

Anywho, all the best with your eat well/weight loss goals, I'm sure you will find a target that suits you, and if you are finding it hard to have that much plain water every day, then don't feel too bad about having juice, raro, flavoured milk, tea, herbal tea etc. Its all fluid at the end of the day, and will still be more than you would have previously consumed.

Best of luck to you, I look forward to your updates!