This is a great joomla plugin that performs directly sharing post on social channels: Facebook, Twitter. It also can display the number of Facebook, Twitter like and sharing even K2 comment number therefore you will have an overview on how effective your post is.
With clean and easy-to-use back-end, you can totally control any parameters in the plugin. You can use Facebook, Twitter icons with default styles or with the specific styles. All you need is to install this plugin and set the classes, the social media button will be well displayed on each post.