Updating the theme will override the old files and replace them with the new ones. So, before you update the theme: if you’ve made any modification to the theme itself (to the files), remember to do that on a child theme so you won’t loose any changes when updating the theme.
(You won’t loose any of your content and settings by updating the theme).
To connect your theme with your license and start getting automatic update notifications, fill in your Artisan Themes Username, Password and License ID in the Theme Updates & License section of your theme by navigating to Theme Options » General tab, and check the “Enable Updates” options.
Then, make sure the Enable Updates checkbox is checked.
That’s it! From now on, you will see any available version of the theme next to your other available plugin updates. So, go ahead and keep your Artisan theme up to date!