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Google has made adding the +1 button fairly simple, but we wanted to provide self-hosted WordPress.org users with a quick walkthrough of the process of adding and enabling the +1 button to their site and their blog posts. We're sure that dozens of +1 plugins will be available in the next few days, but in the meantime, this is what you need to do.
Step 1: Add a Line of JavaScript to Your Theme Files
The +1 button tool page lays out what webmasters need to add to their website. For users who have a standard XHTML website (or are using Tumblr), copying and pasting before the