The best option is to add your license key to enable updates to be pushed directly to your site’s admin. Once your license is activated you can navigate to Dashboard > Updates > find Real Estate 7 > Update, or you can also update from the Appearance > Themes panel.
NOTE: Always be sure to clear your browser cache (shift+refresh) and your server cache if you use that (typically from your WordPress admin bar).
The second options is using FTP to manually update the entire theme folder (recommended) or individual files: