Step 1:

Log in to your WP Admin panel.

yourdomainname/admin

 

Step 2:

Navigate to Divi>Theme Customizer.
You can do this from the Admin Panel menu,

or also from the front using the editing bar.

Step 3:

Select “General Settings” from the Theme Customizer options.

Step 4:

From there, select “Site Identity”.

Step 5:

Under “SITE ICON”, you can click to select a site icon, or change an existing one. Select (or upload and select) from the Media Library.

Step 6:

Publish the changes.