In most cases update does not affect your settings or content but in any case please make a backup before any action and save your translation files . You can use All-in-One WP Migration plugin. If you do not have knowledgeor and your website is live and you dont want to make updates without effect to your customers, our team can help you to do it on a paid basis .
1. You can download the latest version of the theme in your Envato account and install the theme again according to the documentation before this delete old version .
2. Also you can use Envato Market plugin for automatic upgrade theme .
3. Also don’t forget to update the plugins that which belong to author your theme (theme-core , pixautodeal , pixthemecustom , fl-themes-helper and etc) . If you do not have a message about the automatic update for this plugins then do the following steps . On the product page in description CHANGELOG you can see which plugins need to update .
To update this plugins you need: