Answer:
Firstly alot of girls would give anything to be 'thin' so make sure you reallywant to change your body size. If you have been ill then you may need to gain weight so that you can become fit and healthy again. The best way is to eat foods with lots of energy (calories) this will mean you wont be able to burn this all off and it will be turned into fat in your body. Make sure you continue excersing but just eat alot more calories.