It's Very Easy.....
Just Send A SMS
SPICE to 121
You will get a reply:-
Thank you for choosing Aircel.We will offer
you 500 MB Data per month for next 3
months based on your eligibility.To avail this
offer,please dont change the H/S.
You'll get data balance within 24-48hrs...
If u get error message, try after 10mins..