On average, each specific serving requires approximately 1 cup of water.
Using hot water speeds up the reconstitution process, but it is not required. Heaven's Harvest foods can be prepared with any temperature of water, but will re-hydrate sooner with hot water - approximately 15 minutes.
Simply open the pouch of food, remove the oxygen absorber, add water, allow time to re-hydrate and serve.
Specific instructions can be found on the back of each pouch.