Losing weight is a relatively simple process that is hard to do. First off, you have to be at a caloric deficit. It's as easy as consuming less calories than you body burns in a day. The body burns calories for energy and when it runs out of calories, it burns fat. Simple right?
So how do you do this? Well first off, you need to plan out a diet. It doesn't have to be a crazy diet or anything special. You have to start getting used to looking at nutritional values on everything you buy and plan accordingly. Your diet must be under a certain number of calories, say 1500 to 1700 and must revolve around proteins, carbohydrates, and fats. You might be thinking that fats should be avoided but fats are actually healthy for you when you control how much you take in. You should be consuming more protein than anything as your body burns more calories when it digests the proteins since they take longer to digest. Carbs should be kept at a low. These are the dangerous ones especially when you mix them with fats. So to put simply, plan a 1500 to 1700 diet and build it around mostly protein, low carb and fats. Do some research on meals that provide a nutritional value box. Remember, low carbs high protein.
The second and just as important step is to have some form of exercise. You burn calories even more this way. Aerobic and cardio exercises are effective but the most effective workouts to burn the most calories will involve some weight lifting. Just start with light weights and work on doing the exercises right. Do exercises that will get you tired quick and then do them with weights. If you jog, start without weights and progress each week to use like a small dumbell in each hand. The next week, use a slightly heavier dumbell. Use weights with aerobic exercises. If you don't like using weights, you can still do traditional exercising without them but you won't burn as much fat.
Also, sleep at least 7 hours a night and weigh yourself ONCE a week. You should aim to lose a pound at least every day so around 7 a week. But you might gain some lean muscle so it may not always be the case. And if you aren't interested in building muscle don't worry. It takes time to build noticeable muscular results. Besides, the muscle you build will be lean and would only make you look toned and not bulky. Best of luck and don't quit. It's supposed to be tough but results will come if you really want it.