With some it's nearly impossible. Do sit ups and touch your toe. Build up to 100 times, but be careful of your back. You don't want to pull a ligament. The best way might be to just cut down on calories and carbos and do walking exercises.
Do aerobic exercises daily. Cardio exercises will heat up your core temperature and improve circulation, both of which will aid in acquiring a flat stomach. Strive for at least 30 minutes a day minimum, but include one to two days of rest each week. Take up dancing, running, Tae-Bo, swimming, cycling and walking at a good pace—anything that brings your heart rate up. Eat healthier and cut down on junk food. Replace sweets and chips with fruits and vegetables. You'll see a world of difference. Drink water. You should replace all your regular beverages with water, especially soda and sugared drinks. Water will make it easier to lose weight. Consider flavored water as an alternative if you must.Don't eat anything for about two hours before you sleep. Your body slows down when you sleep so you can't digest food properly.