How can I create an Apple ID without a credit card?

See these two documents:

Create or use an Apple ID without a payment method  https://support.apple.com/en-us/HT204034

If you can't remove your last payment method or use no payment  method with your Apple IDhttps://support.apple.com/en-us/HT203905

The only way to create an Apple ID without credit card details is to:

On a computer/laptop -> Go to iTunes Store (or App Store on Mac) -> find a free item/app -> Click "Get" -> when asked for Apple ID, click create Apple ID and following the prompts, when you get to the payment screen click "None" and then verify your Apple ID.