To use Float, you'll need a working version of WordPress installed. For information about installing WordPress, see the WordPress codex.
To Install Float, navigate to Appearance ➝ Themes ➝ Add New ➝ Upload Theme within your WordPress admin dashboard.
Upload the float.zip file located in the theme folder of your download.
Once Float has been successfully installed, click Activate.
Alternatively, if you’re an IT wizard, you can add the unzipped theme folder via FTP to the /wp-content/themes/ directory of your WordPress install.
If you get this error while uploading your theme, it's probably that you're not uploading the correct file from the Float download folder.
Make sure you’re uploading the float.zip file within the “theme” folder of the download, and not the download folder itself (float-envato.zip).