First, the disclaimer: I answered a question similar to this on Askville. This is a cut and paste of what I wrote there.
If you’re willing to change what you eat, how much you eat and your relationship with food, you will set yourself up for success. It’s really the only way. I tried different diets in the past (SlimFast, fruit & rice, etc.) and until I changed the above mentioned things, nothing worked. Oh, they would work temporarily, but that was it.
What worked for me:
1. Portion control. American restaurant portions are far bigger than an actual portion. That can skew in your head what you think a portion should be. Portion guide this link will take you to a guide that you can print to see what a portion really is. (You may have to copy and paste it into your browser to go to it. Not sure if it will make a link.) It covers basic sizes for many foods. The other thing that will help you is to buy a food scale and use your measuring cups and spoons. Use them to measure all of your food. Once you’ve done that for a while, you won’t need to any more. But, until you really know what a portion looks like, you need to measure, measure, measure.
2. Exercise. Get up and move. You can do almost anything for 15 minutes. Go outside, walk for 7 minutes in one direction. Turn around, walk home. (The walk home is always longer!) Can’t walk outside? Walk around in your house. Go to the mall and walk. I would avoid buying any equipment at first. Once you know that you’re going to stick to it, start checking out equipment. Start small. Some adjustable handweights or resistance bands are good things to start with and aren’t super expensive. You need to build muscle and do aerobic movement. Muscle burns more calories at rest than fat does so if you have more muscle, your body will burn more calories for you even when you’re not doing anything. And the aerobic movement helps you to burn fat. If you’re already active, add to what you’re doing!
3. Learn about food. Or at re-learn what food is good for you and what isn’t. Lean proteins, vegetables, complex carbohydrates, low-fat dairy and fruit are keys to success.
4. Find some support. Whether it’s in person or online, find a group of people with the same goals and issues. TOPS (Take Off Pounds Sensibly), OA (Overeaters Anonymous), Weight Watchers, etc., are places to consider. I believe that OA is free, although I cannot swear to that. I’ve lost 70 pounds and I can tell you that the reason that I did it (and will continue to lose) is because of the online group that I found. They understand, listen and encourage in a way that I found beneficial. Online websites include sparkpeople.com and everydayhealth.com . There are others, I’m sure; those are just two that I know.
5. Try to figure out if you’re an emotional eater. If so, check out this book as a source of help.
I hope you find success with your weight loss!