I get an error when uploading the theme "The theme is missing the style.css stylesheet"

When installing the theme ensure you have downloaded the correct zip file from  ThemeForest. Make sure you are uploading the WordPress theme and not the full package. When visiting http://themeforest.net/downloads you will have an option to download the "Installable WordPress file only" select this option, download the file and then upload the file to your WordPress site. See screen shot below.