Stripe + Apple Pay
Visit Apple Pay payment settings:
https://dashboard.stripe.com/settings/payments/apple_pay
Click "+ Add new application" button

Download the Certificate Signing Request (CSR) file.

Hit "Continue" and click, "this page" link. Leave the modal open.
(https://developer.apple.com/account/resources/identifiers/list/merchant)

Once in the Apple Developer website, click the Merchant ID listed.

Click, "Create Certificate" button and follow the steps.

Select No and hit, "Continue"

Upload the Stripe CSR file downloaded earlier and hit, "Continue".

Download the Apple Merchant ID certificate.

Go back to Stripe.
Hit "Continue" to the final modal and click, "Upload certificate".
Upload the Apple Merchant ID certificate.
Hit "Submit"
