Avoid fad diets. It's never a good idea to trade meals for shakes or to give up a food group in the hope that you'll lose weight — we all need a variety of foods to get the nutrients we need to stay healthy. Avoid diet pills (even the over-the-counter or herbal variety). They can be dangerous to your health; besides, there's no evidence that they help keep weight off over the long term.
Here's something else most people probably don't know: Fidgeting is good for you. It's considered a nonexercise physical activity, and it's an important way to burn energy. You get more health benefits if, in addition to exercising, you are a more fidgety, more active person the rest of the day. This means gesturing while you're talking, tapping your foot, just moving around.