Debutify Shopify themes show payment icons in your footer depending on your store's payment settings. You can also add custom payment icons.
How to add custom payment icons
STEP 1
Go to your Shopify Admin and select Online Store.

STEP 2
Select your 3.0 Theme and click on Actions to reveal the option to Edit code.

STEP 3
Scroll and click on the Snippets folder.

STEP 4
In the Snippets folder, find the payment-icons.liquid file.

STEP 5
In the code, find {% for type in shop.enabled_payment_types %} and replace it with {% assign enabled_payment_types = 'visa,master,american_express,paypal' | remove: ' ' | split: ',' %} {% for type in enabled_payment_types %}

The new code has a list of payment providers separated by commas: visa,master,american_express,paypal
. This will determine which payment icons display on your online store. Read Shopify's manual for a list of service providers.
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