FBar Social plugin is a social sticky header bar for wordpress that magically appears at a specific pixel.
The easiest way to install FBar Social is via your WordPress Dashboard. Go to the "Plugins" page and search for "FBar" in the WordPress Plugin Directory. Then click "Install Now" and the following steps will be done for you automatically. You'll just have to activate FBar Social.
Manual installation works just as for other WordPress plugins:
In short: WordPress 3.5 or higher, while the latest version of WordPress is always recommended.