This plugin generates a widget to add Google+ badge on your blog with 'Add to Circles' button.
Add to Circle Widget is very easy to use, just drag it to a sidebar and enter your Google+ Page ID, select layout style, color scheme and save the widget.
By adding this plugin you can grow your audience on Google+ and generate more recommendations for your site in Google search.
Your users can easily add your Google+ Page to their circles directly from your blog.
Add to Circle Widget, also gives you the option to choose the size and color scheme of Google+ Badge.
NOTE: You need to add the code given below in your header.php before
<link href="https://plus.google.com/[Google+_Page_ID]" rel="publisher" />