How do I choose 'None' as my payment method for app downloads on Apple Account?

I can’t upload and I can’t download any apps. The response is my payment method was declined. And i have tried to add other way of payments, but still declined. So, i was advised to choose none as my payment method. And i don’t know how to get to do this. I need help to do it. Thanks.

[Re-Titled by Moderator]

Original Title: Download app