A few weeks ago, I went to the annual Secret Sister breakfast for the ladies in our church. We all exchange names and then give gifts anonymously through the year. This particular day, I had no less than five ladies pull me aside to ask what I did to lose all the weight I lost (about 65 pounds).
Honestly, sometimes I look at myself and can't believe I really did it. I remember buying some size 16 shorts at the end of the summer clearance in 2006, hoping I might possibly fit into them the next spring. They ended up being too big on me by then, much to my surprise. And now I wear mostly 10s, and even have a pair of 8 jeans!
The biggest thing I tell people is that just because it worked for me, doesn't mean it's the right diet for everyone. You have to find something you can live with for the rest of your life. Because a good diet isn't a temporary weight loss fix, it's a way of eating right forever. There are several good ones out there. I used Healthy for Life by Dr. Ray Strand. Other people like South Beach (though I would recommend skipping Phase 1). Another good one is the You diet by Drs. Roizen and Oz, which you can find on the Real Age website.
Mostly what I've done is retrained myself in the way I think about food. And in so doing, I tend to take ideas and recipes from many different sources. Because once I re-learned how to eat, I didn't have to be so strict with myself. If the ingredient list fits my "approved" list (which I carry around in my head), then I can eat it. But even then, I've taught myself not to pig out. Just because something is healthy doesn't mean it's calorie-free!
So I guess the answer to the "how did you do it?" question isn't very simple. The most important thing is to be consistent. Find what works for you and stick with it. If you fall down one day, get up and go again the next. One brownie will not kill your diet, but one brownie, followed by days of self-pity just might.