Well I think it's totally about self-control:
Breakfast: integral toast and a 70-calorie yogurt
Lunch: Fruit (any kind, except banana) and a fish (not fried)
Snack if you get hungry: gum or 90-calorie diet bar
Dinner: Light soup (not a creamy soup, it has too much fat)
Or maybe a cup of special K or cheerios
Some other tips:
DON'T EVER DINNER AFTER 7PM, IT HAS BEEN PROVEN IN INVESTIGATIONS AND THAT HELPS A LOT, TRY TO DINNER BEFORE 7, I SWEAR IT'S AMAZING
I recommend you coffee in the morning, it gives you a lot of energy! (without sugar, or maybe splenda)
Another thing is to drink green tea twice a day, it burns fat and it's good for your health
And of course, do at least 50 abs per day
Good luck