For Google to credit your content as yours and have your thumbnail appear beside search results (which is way cool) you need to do a few steps so that Google can give you authorship. The steps I will go into detail will involve the following.
1. Google Profile – If you don't have a Google profile, go and open one up. It is free and really simple to do. Visit https://profiles.google.com to open one up. If you have a Google Plus Account, you should already have a Profile.
2. Create an ‘About Me' Page on your site where you will put your content. What you will be doing is adding a link back to your Google Profile from within that page using a ‘rel' tag.
3. Creating some content on your site that that will link to your ‘About Me' page.
4. Editing your Google Profile and adding a link back to your Site, in particular, your about me page.
On each link, you will need to add some particular code, the rel=”me” on your about me page and your Google profile page, code and the rel=”author” code in the link on your site that links back to your about me page. Below is a diagram of how I have mine setup.
As you can see from the image above, your about me page will link to your Google profile using the rel=”me” tag in your link and the Google Profile. In your Google profile, you create a custom link that links back to your about me page with the rel=”me” tag, this is easy as Google places this tag automatically. Then you need to create a link on every page of your site that will link to your about me page using the rel=”author” tag.
I have created a video below showing the process I use.