Below is a short explanation that will enable you to add a ShareThis button widget to your WordPress blog posts. The snippet below will work both on individual post pages and multi-post pages like categories, archives or custom page templates.
As you can see there are three important parameters here:
st_url: The link to the shared post
st_title: Displays the title
st_image: The URL of the post thumbnail
Using these parameters you should be able to customize this snippet to display whatever data you want it to. So there you have it, no need to install a plugin for this very simple task!