One tip: Eat eggs for breakfast, with as little added fat as possible. If you don't have time to cook them, cook some hard-boiled eggs for the fridge the night before so you can eat them in a hurry the following morning.
Starting off with a protein early in the day suppresses the carb cravings throughout the day.
Get a little more carbs in this meal, not just eggs. Breakfast is the meal that starts your day, make sure that you're not famished and not bloated.
For lunch, it depends on what you can carry and how much you're going to exercise for that day. On average, walking around and doing everyday stuff burns around 600 calories (I think it's a little bit more, maybe).
You should probably eat some vegetables + meat with rice/bread. So it seems like a Subway sandwich would do good for lunch.
Dinner. For me, I have no choice since I can't eat lunch at school or eat a huge breakfast so I eat a very big dinner. It's not really proper, but I'm still slim (=P with a wee bit more baggage, no 6 or 4 pack, mind you) since I do lots of tennis and running. If you're not restricted with very long lunch lines and will be able to eat lunch somehow, dinner shouldn't be heavy since you're going to sleep right after and those calories wouldn't go anywhere. Eat some chicken maybe (I think chicken is the least fatty among beef, and pork) or fish. Then, put some veggies in there since they're a pretty good source of protein, even though it may not look like it (my health teacher says). Not much carbohydrates, perhaps, since you won't need much calories for sleeping (but you still use calories for breathing/ your heart).
Add fruits in any meal.
Another option would be eating less in your meals, but having frequent SNACKS (shouldn't be large) to sustain you for the day. Snacks can be:
Produce: Fresh fruit (ex. apples, bananas, oranges, grapes, or and blah blah berries). Some portable veggies such as baby carrots, celery, or cherry tomatoes.
Breads (great for packing glycogen in your muscles): Whole grain bagles, bread sticks, or whole wheat pita bread.
Cereals, Granola Bars, Cookies, crackers.
Dried fruit, nuts, and energy drinks work very well too.