Do backups before any theme update, or major plugins update.
Nothing stands still: the updates for WP and plugins are constantly released and they are included in our theme. We supplement our theme with new features and fix all the issues. Because of this owl-themes team regularly updates themes. We recommend you to use always the last theme version to avoid the issues with incorrect theme functioning. While the theme update the theme files will be rewritten and if you made any changes directly in them, the changes will be lost.
So, if you are planning to customize your theme, we insistently advise you to use Child Theme’s ( digrand-child.zip ) style.css file, if your changes affect only css styles. More information https://codex.wordpress.org/Child_Themes
The theme update affects only the theme files and do not influence the data base. But, to avoid any difficulties, please, do the backup of theme files and data base before any update.
Follow the steps below to update theme through FTP:
Download the zipped package from ThemeForest and extract to your desktop.
In the extracted package you will find archive digrand.zip , which is the WordPress theme.
Extract zip file and upload only extracted digrand folder to /wp-content/themes/ folder on your server with overwriting.
Please, re-save your Digrand options after upgrading the theme. Navigate to admin panel > Theme Options and hit Save changes.