First of all, make sure you're properly hydrated. It isn't just drinking water before meals to feel more full (although that does work), but getting enough water throughout the day to make your body work properly. If you are not properly hydrated, your kidneys are unable to filter your system at the optimal level, and your liver will start taking over some of their function. The problem is that the primary function of your liver is to metabolize the food that you eat. If it is busy doing the job of your kidneys, it is unable to metabolize properly, and your food will end up stored as fat instead.
Second of all, NEVER go on a diet plan that involves cutting out all of any food group. Your body needs all of the complex nutrients included in a well-rounded diet. Instead, work on replacement. Switch your protein intake to lower-fat sources that include other important nutrients (seafood that's high in Omega 3, for example). Do not give up carbs and sugar; your body requires them for energy. You can almost certainly cut back on them, because American diets are typically much heavier in carbs than they need to be, but the key is to switch to healthier versions. Look for higher-fiber substitutes to the standard yeasty breads and white flour pastas and plain white rice. Not only will they typically have more of the vitamins and nutrients you need, but they will fill your stomach faster and extend the feeling of fullness longer, as well as maintaining the health of your lower digestive system. While you want to strictly limit your intake of refined sugar, there are numerous alternatives out there, not to mention the naturally-occurring sugars of things like fresh fruit.
Control your portions. Your protein at a meal should only be about the size of a deck of cards. Your priorities at meals should go protein, dark green and leafy vegetables, then other brightly-colored produce (a good rule of thumb is that the more vivid the color, the more nutrient-rich it is), then carbs. Eat slowly. Not only will you enjoy your food more, but your stomach will have time to tell you when it's full before you have the chance to overstuff it. Recognize that you want to stop before you reach the point of "I couldn't possibly stuff in another bite".
Be active, and work your muscles as well as your cardio. Without chemical help, you are not going to get big, bulky muscles, and strong muscles are important to function, metabolism, and a sense of good health and well-being. Find activities that you like. If you are dragging yourself to a boring round at the gym and dreading it, you are more likely to skip it every chance you get. Take a dance class, or a self-defense class, or go for long walks someplace you really enjoy, anything that gets you moving that you'll do willingly.
Lastly, change your mindset. Don't think of it as "I have to exercise, I have to give up foods, I have to lose weight." You will sabotage yourself with negativity and stress yourself out. Think of it, instead, as enriching your life by making yourself feel better, engaging in fun new activities and interests, and exploring new, healthier cuisines.
