Follow the steps -:
1) At First Download Hammer Vpn
2) Now Dial *567# And Activate Any Facebook Pack.
3) Now Install Hammer Vpn And Open.
No need any registration to use hammer vpn.
4) Now select Server2 on HammerVPN.
And Set following details on HammerVPN to enjoy unlimited free 3g internet on airtel sim
Rport – 53 & Lport – 0 and select UDP [at last] {working in many states with 0 balance}
OR
Rport – 53 & Lport – 33019 and select UDP [at last] {working in many states}
OR
Rport – 53 and Lport – 0,49201,49202 and select UDP [at last] {working without facebook pack in many states}