To help establish customer trust, you can include a security badge in your theme, and link it to Shopify's documentation on Payment Card Industry (PCI) standard compliance. Depending on your theme's color scheme, you can use a light-colored, or dark-colored, version.
Add security badges to your theme
Security badges are often included in the footer or near the Add to cart button on product pages. However, they can be included anywhere you have access to include HTML.
The following examples show the HTML to include for each version of the badge: