Don't replace meals. Eat lots of lean meat and avoid carbs, sugar, and fat. Don't kill yourself trying to avoid carbs and fat, just make sure your intakes for both are lower. If you really crave carbs, give yourself 1-2 carb days a week. Do avoid sugar like the plague.
Moderate weight lifting and cardio (3x a week for each) should be incorporated. Otherwise, you'll just lose weight and still be soft and pudgy all over.. which is probably not what you want. If you only want to lose weight so the scale shows a lower number, you can skip the weight lifting.
Edit: Nm, no cardio for you. Moderate weight lifting it is! Don't be lazy!