This plugin inserts Google + 1 Button in your site from the Dashboard. No code necessary!
You do not need to edit the theme. New GooglePlusOne is the easy way to insert the Google+1 in your site without have programming knowledges.
Google + 1 will be added automatically in all your posts and pages. You can customize the place where the button will appear, by changing its position or by choosing another HTML element which will contain it.
Also, you can choose to have a single Google + 1 button in your site’s header.
If you have a bit of HTML knowledge it would help.