If you bought theme from ThemeForest, go to your themeforest dashboard >> downloads. If you bought theme from Ninzio Themes, go to your account, and from available downloads, download the latest version of the theme. From there you can find new version of theme. Download it. Use FTP to update the theme. For FTP you need to unzip the zip file and upload to wp-content > themes. You will not loose any data during update, however it is recommended to export theme options (WordPress admin >> Apperiance >> Theme Settings >> Import/Export “ choose export the file).