BMI or Body Mass Index is an important indicator of your physical stature.There are a number of things that you can try to increase your bmi. First of all, to increase muscles, focus on a protein diet. Increase the intake of fiber in your food. Concentrate on drinking milk and juices. Drink as much water as you can, don't restrict yourself to 8 glasses. The best formula is to drink banana shake for increasing your BMI. Also, since you need more muscle and fats, work out. If you can not join a gym, try working out on your own by buying a workout CD. Include running and jogging in your routine.