There are two different issues here: the marks whilst you actually have Chicken pox, and those marks that are still remaining after you have had chicken pox.
For marks that you have during Chicken pox is:
"Do not touch those marks with dirty hands and while washing your face handle them gently. Never try to scratch it, because it will do more harm to your face. You can use some homemade remedies to get rid of the chickenpox marks. One of the best homemade remedies for chickenpox marks is to apply ground margosa leaves and turmeric on the affected areas. If you use this remedy for few weeks, it will definitely provide a positive result. The chickenpox marks are treated by various treatments. You can take baking soda bath to cure these marks. Use calamine lotion on the skin dotted by chickenpox marks. You can also take some capsules and benadryl liquid by mouth if the problem is too harsh. Vitamin E is the most needed vitamin for skin, so you can apply the vitamin E oil over the skin affected by chickenpox. If you apply the sandalwood oil on the chickenpox marks from the beginning of the chickenpox, the marks will go away quite soon. " 
Chicken pox marks that remain affter you have had Chicken pox are actually scars, and therefore they do not naturally disappear. There are surgical treatments such as metnioned in . Although there are potential means of reducing the visibility of such scars which include creams. .