Question: It's my prom in a few months....

elliptical machine or pilates :) and lots of water.

Exercise burns fat indiscriminately -- meaning you lose fat from wherever you're likely to lose it first, not from whatever area of your body you are exercising.

The fiber suggestion was good; celery is a really straightforward approach to getting fiber, it works quickly, and because it takes so much energy to digest, it has a (very slight) negative calorie intake. You burn off more calories trying to process it than the celery gives you.

Keep walking, and change your diet. Eat fresh things, emphasize fruits and vegetables and lean meats, and don't drink anything that isn't water or 100% tea or NATURAL fruit juice. Anything with added sugars (or corn syrup) isn't going to do you any good.

First off, women are supposed to be curved around their lower abdomen, not completely flat. If you have extra fat around that area, the only way to really get it to decrease is to lose weight. There is no such thing as spot reduction. You can tone the area by doing abdominal exercises.

sweetie as much as i hate to tell you this its all about the cardio no matter how much you work on your tummy as long as your not doing cardio the weight will stay you have to get your heart rate up run on the tread mill get on the bike, anything that will make your heart rate go up and you should sweat a great deal as well

Ok, so let me give you few little advices, if you need more, just don't hesitate to contact me!
Do drink at least 1L/20kg every day! Our body is made by water and for the proper functioning of your cells you need water. Much water than that won't harm you at all, that's just the minimum. Forget about alcohol! Many people don't really understand how much cal. there are in only 50ml! Forget about sodas too, no light cola or things like that! Only water and yeah, green tea and a bit of red wine are helping for burning the fats out, they're just pulling off the fat from the mucous membrane of your stomach. The green tea also helps rid of cellulite with the proper massages and exercises.
Do consume more fruits like oranges, grapefruit, apples and vegetables like asparagus, tomatos, peppers, pumpikn and all products from the bean family - good source of proteins. As well as soya products. You can eat potatos, of course, but again in small quantities, separated meal and preferably not fryed but boild. Do use flaxseed oil instead of all other oils. Forget all fast food chains! Instead of corn flakes or all other fast prepared breakfasts, use oats, but raw.. Just boil water and then pour on the oats. This combined with milk is the perfect protein breakfast to start with your day. Cut off all the sugar! Instead use honey, but in a separated meal because it's transforming fast into energy and if you consume it along with rich of carbohydrates meal, your organism won't transform the carbs, but collect them in your body. Forget the strict 3 times a day eating! Eat in small quantities but more often.. Sometimes I eat 6-7 times a day.
Consume less red meat and instead concentrate on white chicken meat and fish meat. Use low fat yogurt and dairy products. Consume at least 2whites and one yolk per day. The white is a great source of protein which you need for building your muscles.
So far, so good. That was for the eating regime. Now for the trainings.
Since you have experience in trainings, I do recommend you the one day on/one day off program. Which means you train one day and you leave your body rest one day.
Regarding to the fact you don't have much of a time, try combined intensive work outs for max 45min. You don't need more! The idea is in the repetition! Not in the long time trining!
For the lower part of your stomach try:
1.Laing down and lifting up your legs - 20times
2.Relax and take your breath back - up to 10sec.
3. Reverse crunches - 20times.
4. Relax
5.Side cruches - 20times (they're helping to build up all your side muscles and get some loading on your lower muscles)
6.Relax
7. Plank - http://www.youtube.com/watch?v=9Ar2iRusnnc
8. Relax
9. Hanging leg raises - If you have a place to do it. - 20times.
10.Relax
Repeat all- 3-4times.

You can make different combination of those exercises or you can chose out of them those that have the greater influence on your lower abs.

And those are the main things. If you're interested, see also those:
http://www.youtube.com/watch?v=tVog4y4Ziww&feature=related

Good luck and remember: the persistency is the key! :)

http://www.youtube.com/watch?v=WlTvnfOr6_Q
It's a video on how to do reverse crunches. I tried it for about 5-10 minutes and it was improving already. These type of crunches work out the lower abs rather than the upper abs.

And, as the other commenters have already pointed out, you will look beautiful no matter what!! :]

Get more fiber!! A lot of people don't realize how much extra weight they carry around in their colons. It's so important to keep it cleaned out; you will lose weight and feel so much better. There are lots of ways to do this- one is simply eating more things with higher amounts of fiber. There is also bran, usually called "Whole Psyllium husk." You can get it at any health food store; just mix a few tablespoons in a small glass with some orange juice and drink it every day. The texture is slightly off-putting, I guess, especially if you haven't tried it before, but it has NO TASTE. Especially if you use plenty of orange juice (or any juice really, but I only take it with orange juice.) it's pretty easy to deal with. There's this stuff they make called Fibersure, which is a fine powder you can add to pretty much any food or drink, and it's supposed to be tasteless but I haven't tried it so I don't know how well it works. Drinking tea works really well for me, namely green tea (my fave is Starbucks!) and also regular lipton tea, it always cleans me out. There are also special detoxifying teas, haven't tried much of those but they're good for you. And just basic diet and exercise. I wouldn't recommend going to any extremes for dieting because it sounds like you're not really carrying that much extra weight-just try to cut out fast food, soda, things like that. I know it's really hard. :( If you walk a lot, that's good. And the thing about crunches that most people don't know- crunches will tone your stomach muscles BUT if there is a layer of fat covering them you will never see them no matter how many crunches you do. You need to do cardio in order to burn the fat- walking, running, or basically any activity that gets you to break a sweat and gets your blood pumping. I hope this has helped; have fun at prom and as the first comment said you will look gorgeous no matter what!! :D

Stay away from carbonated beverages and salt if you can b/c they tend to make you bloated... Also even though they're crunches the bicycle crunch works really well for me. And worst case scenario although they may not be flattering -- spanx are amazing :) Have fun at your prom and no matter what you'll look beautiful!!