Well, let me give one advice:
[HEADING=2]Don't diet![/HEADING]
Diets, in the long run, are completely counter-productive. Loosing weight is dead-simply; burn more calories than you take in. Keeping that weight off is just as simple but still the part where many people go wrong. What you need to do to keep yourself on a healthy weight is change your entire lifestyle. And while they're simple, neither are easy, that's an important distinction.
What it all boils down to is to not do anything you won't be doing for, basically, the rest of your life. No über-intens exercise plans you'll basically only do for a few months. No retarded eating habits you'll break when you're on your target weight. Don't expect it to go quickly either.
Here are some basic things:
- Eat healthy, varied and regularly. Three square meals a day made from healthy ingredients with reasonable portions. If you're having trouble deciding what kind of portions are right, you can use a calorie counter for a while. Just don't get obsessed with it.
- Have an exercise plan that's fun, and don't over-do yourself. 2 Evenings in the gym combined with an hour and a half walk? Sounds good. Keeping a rhythm in it helps as well.
- Don't scrap treats entirely. There's absolutely nothing wrong with a nice Snickers bar, some crisps or something like that every now and then. It's important to reward yourself, just don't over-do it, remember that moderation is key. It'd also help to eat more sweet fruits as treats. Strawberries, grapes, apples, bananas...omnomnom.
- Fuck diet products and fuck crap like that "no carbs" bullshit. Would you do that your entire life? Chances are; no, so ignore them.
Really, there's not much to it, but remember that while it's simple, it ain't easy. If you're used to a non-caring, slouchy and unhealthy lifestyle, changing that to a healthy and balanced one is going to take a lot of willpower and frustration as it won't go quickly. Remember what you're doing it for and you'll be alright.