inter-stella----
It seems that it's different for everyone, but for me, I thrive on the control that I get out of planning out my meals and exercise. When you're not consciously thinking about what you're putting into your body, you often aren't paying attention to how your body responds to it. BUT, when you really start to pay close attention to what you're feeding your body, it's easy to see the results of your choices in plain view! I was never aware that my body changed so fast just based on my activities and the foods I was eating until very recently!
Also, it helps me a lot to make little mini-goals for myself. Even if I don't meet them (I missed my second one), I usually come close, and that means I'm better off than I used to be! The prospect of trying to lose 76 pounds (which is my ultimate goal) was too overwhelming. So, I find it helpful to break it up into manageable slices... How do you eat an elephant?...
Third, I try to limit negative self-talk. I know it's a habit, and we're always so hard on ourselves that it's really hard to stop doing it. BUT, think about it this way: society is full of images communicating to you that you're overweight, not attractive, etc... What you say to your own self in your own mind is ENTIRELY up to you. Sometimes you have to be a cheerleader for yourself!
Fourth, pick a plan that you can live with. Any diet is bound to fail if you HATE it from day 1. Think of a healthy way of eating that you can feasibly live with for the rest of your life, and let that be your "diet".
For motivation, this website works wonders. There are tons of people here who will help you when you're having trouble and cheer for you when you succeed. It's worked wonders for me so far! For avoiding temptation, I struggle. I often think to myself "do I want this _______ more than I want to be thinner?" and the answer is usually no. If the answer is yes, then I go ahead and treat myself. This website is good for keeping you from caving in to your temptations, too. I speak from experience when I say that it is EMBARRASSING to have to come in and report that i completely pigged out one day. It's like an entire network of accountability partners!
Finally, understand that setbacks are part of the process. You may not lose every day or every week... Learn from your setbacks and move on. Do not beat yourself up. The only way for you to fail is to quit.
Best of luck to you. Please stick around the website because it's an invaluable resource. The people here want to help you succeed!