I have been keeping fit primarily with weights for 27 yrs now, and have provided personal training to many people over the past 20 yrs. I can tell you with confidence that in my experience, counting water and calories works!
I've found that most women burn approx. 100 calories per hour. Most of us are awake 15 hrs per day. If we drink 8 eight ounce glasses of water per day and take in approx 1300 calories per day, this gives us a caloric deficit of approx 200 calories per day BEFORE exercise. Can't help but lose!