Access to your Themes setting
From your Shopify admin, go to Online Store > Themes
Duplicate your Current Theme
In the current theme, you will toggle the ... button to open the actions menu. Then, click Duplicate so that you can create a copy of your theme, which is named Copy of [Original theme name]
Customize the Duplicated Theme
Click Customize to open the theme editor where you can make changes as you want.
Test the App and Make your Changes
You can activate App Embeds that add functionality without being visible to customers. These can be managed in the theme editor as well.
Preview your Changes
Use the preview option to see how your changes look before and after changes. Hereby, you can decide whether or not you've satisfied with the settings and appearance of AOV Free Gift in your store without making them live.