Publish, Save, or Schedule Your Customizer Settings
Once you have made the necessary changes, you need to apply them to your site. Otherwise, all your hard work will be lost.
Go ahead and click on the Publish button to apply the changes. Once done, you can click on the close button, present at the top-left corner of your screen, to exit the theme customizer.

What if you need more time to finalize your new design? In that case, you can save it as a draft and even share your new design with someone without giving them access to your admin area.
To do that, you need to click on the gear icon right next to the Publish button. This will open up the Action panel.

Here you’ll find three options: Publish, Save Draft, and Schedule.
You need to select the Save Draft radio button on the Action panel and then click on the Save Draft button to store your changes.
You can now copy the preview link and share it with others to get feedback.
On the other hand, the Schedule option allows you to publish your changes on a specific date and time. You can use this option for scheduling your theme changes to go live at the time when you receive the least traffic.

Lastly, if you want to reset the unpublished changes, then you can click on the Discard changes link on the Action panel.