Shopify
After adding Sezzle to Shopify, see How do I add widgets to my product and card pages? (App Blocks method).
WooCommerce
See How do I set up Sezzle on WooCommerce? (Video tutorial) or technical documentation for WooCommerce here.
BigCommerce
See How do I get started with Sezzle and BigCommerce? (Video tutorial) or technical documentation for BigCommerce here.
CommentSold
See How do I add Sezzle to CommentSold? (Video tutorial) or technical documentation for CommentSold here.
Other eCommerce Platforms
If you are using an eCommerce platform that is not listed here, please reference https://docs.sezzle.com/#plugin-guides for any troubleshooting recommendations.