Drink at least 2 quarts( liters) of non-caloric water each and every day.  

WHY - So much ??

With weight loss, the body produces a bunch of extra chemicals.  Mainly ketones.  These are eliminated by way of the kidneys.  To facilitate their removal, you will need to provide extra water to help the kidneys to do their job.  Equally well, there is increased needs for water to help the gall bladder to do it's job.  Besides, water is necessary to eliminate fat from your body.  And finally, you are going to need water to get rid of the sweat that you generate during the Exercise part of this equation.

See Wayne Smith's surprising analysis for the need of Exercise and Water.

Why non-caloric?

Easy to answer.  Why in heavens name when you are trying to lose weight, add calories to the system?  There is no reason for fruit juice, soda or any other calorie bearing liquid.  The body does NOT need the calories.  You don't need the calories.  And certainly, the weight loss does not need the calories.  

I will lighten up somewhat on non-fat milk and drinkable yogurt.  The amount of protein, and calcium that you get from non-fat milk and drinkable yogurt far out weighs the caloric intake.

You also need to know that during the weight loss phase, do not drink water and eat at the same time.  Drinking water while eating will cause the food to be watered down and you will be able to consume more than you would by not drinking and eating at the same time.  Most people suggest that you stop drinking 20-30 minutes prior to a meal, but I suggest maybe 5-10 minutes prior is fine.

See Wayne Smith's surprising analysis for the need of Exercise and Water.

The three keys to success with the band

Exercise

Protein

Water