If you want to update any theme or plugin directly then you have to follow these steps one by one.

• First of all you have to upload and Install “Easy Theme and Plugin Upgrades“on your existing WordPress website.
• Then activate this plugin
• Then download the latest version of theme/plugin from XYZTheme.
• Open your Admin Panel / WordPress Dashboard.
• Add new Plugin
• Tab on the “Upload Plugin” button present at the top of the page.
• Select the zip file with the new plugin or theme version to install.
• Then click on “Install Now” button.
• After the process is successful, press “Activate” plugin.