For this , you have to create a new message center from your phone's
messaging options . Use this number +919810051905 as the message center
number . Now I assume that you are on a Nokia mobile phone . Browse
through your phone settings and find out packet data from connections .
Now change the option for Packet data connection from when needed to
when available and access point as Airtel live .Save the settings .
Now
you can send unlimited free SMS from your Airtel mobile phone . And
when each time you send an SMS , remember to add a zero at the
beginning of destination number .