If you feel that your stomach is big, first identify whether the abdominal fat lies outside the abdominal wall or inside the abdomen. If you pinch it with your hand to see, put your index finger on your belly button and your thumb on the right side of your belly button, then pinch it. If all can be pinched up, it is extra-abdominal fat, if only a little pinched up, it is intra-abdominal fat. If it is extra-abdominal fat, go through effective exercises to lose the big belly, such as sit-ups, etc. If it is intra-abdominal fat, you need to lose your belly through eating habits, such as a low-fat diet, etc.