Hi Arundhati,
It would be hard to tell you what to do after your workout, because it depends on various factors like type of exercise you are doing, intensity and the duration of your workout and the most important purpose of your workout like weight loss, weight gain, improving fitness level, maintaining fitness etc. In general you need to end you work out with a cool down exercises. Cool down exercises not only helps in faster recovery but also prevents body from unwanted post workout body stress and many injuries. Duration and type of cool down primarily depends on your workout. But make sure stretching is the part of it. Once you have done with it you can go for some relaxation postures and breathing exercises. Post work out meal is of great importance to restore your body to the pre workout status. Your post work out meal should be rich in carbohydrate which will replace the glycogen stores depleted during the activity. A fast digesting protein like oats, whey protein and other protein shakes which will helps in repairing the wear and tear of tissues. Along with this take care of bodies hydration and electrolytes level. Rehydrate your body with water or juices or some sports drink.