Drink lot more water.
Drink Green tea that will help you to reduce weight.
Drink lemon juice with warm water. You can drink this after breakfast, lunch.
Eat more spicy elements like ginger, garlic, onion, etc. in your food. These food helps to digest the food even faster.

Swimming is the best way to reduce weight.
Try to involve in a game like tennis, badminton, etc.

The below link is useful for you.
http://www.atozanswer.com/forum/viewtopic.php?f=37&t=7

It is good that you have sought the help of Yoga to bring your body back into shape. While your practices and measure to eliminate excess weight or what you do is important, what you shouldn’t do is just as important.

* Don’t resort to weight reduction pills or powders of any sort and please avoid crash diets. We shall prescribe you a simple diet that is healthy, easy to follow and will deliver the desired results. See a nutritionist or dietician, if you must, but preferably one who knows and practices Yoga.

* Never skip meals. This makes you overeat at other times. So, by all means eat three or even four times a day, but eat light and sparingly.

Yoga Exercises

Standing Position

# Tadasana (Palm Tree pose)
# Parvatasana (Mountain pose)
# Trikonasana (Triangle Pose)
# Ardha Chakrasana (Half Moon pose)
# Padangusthasana (Toe to hand pose)
# Padahastasana (Forehead to knee pose)

Sitting Position

# Janu Sirshasana ((Forehead to single knee pose)
# Paschimottanasana (Forehead to both knees pose)
# Ushtrasana (Camel pose)
# Gomukhasana (Cow face pose)
# Simhasana (Lion pose)
# Marichyasana (Pose dedicated to the sage Marichi)
# Ardha Matsyendrasana (Half Lord of the Fish pose)

Supine Position

# Purvottanasana (Inclined Plane)
# Matsyasana (Fish pose)
# Pawanmuktasana (Wind relieving pose)
# Navasana (Boat pose)
# Chakrasana (Wheel pose)
# Sethu Bandhasana (Bridge formation pose)
# Halasana (Plough pose)

Prostrate Position

# Adho Mukha Svanasana (Downward Dog pose)
# Bhujangasana (Cobra pose)
# Dhanurasana (Bow pose)
# Shalabhasana (Locust pose)

Inverted Position

# Viparita Karani (Legs against the wall pose)
# Sarvangasana (Shoulder Stand)

Balancing Position

# Vrikshasana (Tree pose)
# Garudasana (Eagle pose)

Pranayamas (breathing exercises)

# Kapalabhatti (Skull cleansing)
# Anuloma-Viloma (Alternate Nostril Breathing)
# Suryabhedana (Right Nostril breathing)

Kriyas (Cleansing techniques)

# Jala Neti (Cleansing Nasal passages with water)
# Sutra Neti (Cleansing Nasal passages with rubber catheter)
# Vaman Dhauti (Cleansing stomach by vomit water on empty stomach)

Yogic Diet

This is very important, if you wish to get back into shape and develop a healthy, slim and shapely physique. Let your diet be Yogic and Sattvic (pure, light and predominantly vegetarian). This means plenty of raw foods – salads, sprouts and seasonal fruit – vegetable juices, dried fruits and loads of water.

Avoid potatoes, peas, chick peas, grams, peanuts, all non-veg fare, fried, fatty and spicy foods, junk / fast foods, packaged foodstuffs and confectionary products. Also keep away from milk and milk products such as cheeses and butter. But you may have plenty of diluted buttermilk prepared from skimmed milk. Avoid snacking between meals and, as mentioned before, never skip a meal.