I hope everybody is Already enjoying the MTN free call, but if not follow the step:
1. Dial *142#
2. Check the options given to you..
If you see something like
1. Pay 40 naira to make call for 24 hours
2. Pay 150 to make MTN TO MTN calls for 7 days
then choose any option either 1 or 2
Note: other people may see 30 naira and 150 naira you may choose any one of your choice.