For this trick you need to have two mobile phones, one to verify the number and other to use WhatsApp on it (Without SIM Card) and a SIM Card with mobile number that is not registered on WhatsApp.
This number is used to configure your WhatsApp on Mobile that doesn't have SIM Card.
First of all connect your mobile to internet through Wi-Fi or Dongle, download WhatsApp on it. Then register with the mobile number that we discussed earlier. Now you will see a message with verification fails, don't worry you will receive the verification code within 10 minutes. Now you will get an SMS with verification code to the registered number, select 'call me to verify the code' option and verify the code. That's it now can use WhatsApp on your mobile without having a sim card.
