Google Store allows you to skip adding a credit card during the payment step.

1. First open the Google Play Store client on your mobile phone.

2. Click Create New Account on the Add Google Account interface.

3. Then write your name on this page and click the Next button.

4. Then fill in an email prefix username that you like and is easy to remember, and then click the Next button.

5. Then fill in the login password and click the Next button. Then click to select a security question, set an answer, and click the Next button.

6. Set the skip button at the payment point and complete.