Follow the below simple steps.
1. Dial *166# ,get a success mesage that you are on club 10.
2. Call 14120 , follow the voice prompt,press 1 for english,then press 1 to get 100 from airtel.
2 . After that you would get a success message from airtel, just check your bal. You will see #90 ,dont panic .
3. Make call with the airtime till your balance remain #54.00 or below.
4. Now dial *123*4# you would see the magic.
NOTE: YOU CAN ONLY MAKE AIRTEL TO AIRTEL CALL WITH THE BONUS.