How can i lose the weight i gained during pregnancy and keep it off?

During pregnancy, i gained a fair bit of weight, now whatever i lose, goes straight back on, all the weight is around my waist which my waist has geon from 28 Inches to 42 inches. does anyone have any ideas to lose the weight and keep it off?

The most important factors having to do with your weight are, in my opinion:

1. Eating intervals
2. Eating times
3. Food nutrition
4. Food portions
5. Exercise

You'll notice that while portions and exercise are what people generally try to change when they want to lose weight, it will almost have no effect on their weight compared to the others.
1. Eating intervals are basically the frequency of eating. NO SNACKS. The no-snack policy is the best thing you can do to lose weight. Eat ONLY three times a day. My family has been trying this policy. I went down from 145 to 134 in a matter of months. Give your body time to use the stuff you feed it before feeding it more.

2. Eating times are also important. Never, ever eat anything after 7:00 at night. When you eat, your body can do two things: burn the food as energy or store it as fat. Which do you think it will do if you eat and then go right to bed? Another thing you should keep in mind is what time you are eating what. Eat the most in the morning, less at lunch, and least at dinner.

3. Food nutrition. Take the time to find out about this area of health. And don't be fooled by the front of the box: "Low Fat!" or "Low Carb!" may still have lots of things that are bad for you. The real information about the food is on the back or side under a little tab called "nutrition facts". BTW, it's NOT worth eating sweets or anything else you KNOW is unhealthy. It may seem like you're not "living a little" when you refuse chocolate and candy, but in reality not eating that stuff will give you more energy and a better body with which to live your life.

4. Food portions. Like I said, eat the most in the morning, less at lunch, and least at dinner. Americans are extremely susceptible to eating too much food. Their stomachs stretch to be able to hold more food, and it's just unhealthy. Your stomach is probably roughly the size of your fist, or at least it should be. Keep that in mind when eating. When you aren't hungry anymore, just stop eating. Also, remember that the food you eat is sort of "compressed"--squeezed down in size by your teeth and such, so a piece of bread the size of your fist won't be nearly that big when it reaches your stomach.

5. Exercise. While this has very little effect on your weight compared to what most people think, it can help you lose weight. But mostly it effects your health by helping out with cardio so you don't end up needing a bypass surgery. It also builds up muscle. Make sure you change your exercise now and then. It's not good to keep on the same routine or to exercise steadily. Constantly try to surprise your body with new and strenuous exercises.

Try to drink more water, it will keep you hydrated and help you to feel more full.
Take a walk every day with the baby in the pushchair. Walk briskly for 20 mins or more.

Exercise, and a healthy diet will help you lose weight, if you are consistent.