In RepU, open your widget, choose light or dark and left or right, then click Copy next to the embed snippet.
In Shopify, go to Online Store, then Themes. Click the three dots on your live theme and choose Edit code. Open theme.liquid and paste your code just before the closing </body> tag.
Need more detail? See the official Shopify guide.
Click Save, then open your live store to see your Google reviews.
Check your live site in a private window, not the editor or preview. A domain-locked widget only shows on your own domain.
Theme updates can replace theme.liquid, so check the code is still there after updating your theme. The Starter plan does not allow theme edits.