Updating a theme means replacing the current theme with a newer version. You should always keep in mind that if problems occur during installation, they could cause the whole publishing system to malfunction. Therefore we recommend backing up your web and thus avoiding any inconvenience.
Updating a theme is very quick and simple. All you have to do is click on Activate under the theme preview in the administration interface. WordPress then replaces your current theme with the updated version. Pay attention to the fact that if you have made any manual changes to your theme, all of them will be lost. When you’re updating your theme, the theme folder is temporarily renamed and when the update is finished, the folder name is changed back to the original version. So everything in the original folder (the previous version of your theme) is deleted and replaced by the updated theme.
Using FTP to update your theme is also very easy. Load the downloaded theme update via FTP, e.g. under a different name. Save it into the following folder: /wp-content/themes/. Activate the updated theme in the administration interface and you’re done.