Stop eating junk, fried, sweets and soda. Stop drinking alcohol. Start eating vegetables, fruits, cereals, salad and other healthy food items. Increase your protein and fibre intake. Don't overeat, eat sensibly in small portions and 5 meals a day. In workout, start doing running 8 miles a day. Do swimming 30 mints (4 days a week).
Make your body active and increase your stamina.