In this video I show you my exact step-by-step process to connect Google Tag Manager with Squareup.com (Square Online) without needing any developer help. After you complete your Square registration and you land in the Square Online interface, I go straight to Settings and then Tracking Tools from the left side. This is the area where Square lets you add different tracking and verification options like GA4 Measurement ID, Google site verification, Pinterest tag, Meta/Facebook Pixel ID, and Bing verification. My main target here is GTM, so I scroll down to the Custom Header Code section and add the GTM container code in two parts—head and body—exactly like Google Tag Manager provides. I copy the head snippet from GTM and paste it into Square’s custom header code, save it, then add another code entry for the body snippet and save again. After that, your setup is basically done, and you can preview the website and check if GTM is firing using Tag Assistant (I didn’t show it because it was a client site). If you want clean conversion tracking later (GA4, pixels, CAPI, etc.), this is the first correct foundation.