Customize your theme in the Theme Customizer Panel and see all changes live without page reloading.
Please follow the steps below:
How The Theme Customizer Works For Users
Please note that the screenshots are for explanatory purposes. Content look may change.
Step 1:
You can load the Customizer in three ways:
1. Dashboard > Appearance > Customize
Step 2:
This brings up the Theme Customizer in the left column, along with a preview of your website on the right.
The Customizer options are shown side-by-side with a preview of your website, so you can test the effect of changes.
Step 3:
To make changes, all you have to do is select each of the available options and edit their settings.
Once you’ve made the changes you want, you must click the “Save & Publish” button. Until this is clicked, none of the changes is reflected in the live website. This means you can play to your heart’s content without your visitors seeing your experiments.
https://codex.wordpress.org/Theme_Customization_API
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