Linking your blogs to your Google+ profile allows you to easily share your blog posts to your Google+ stream, right from your Blogger dashboard. In addition to getting access to existing and upcoming Google+ features, linking your blogs to your Google+ profile will give your readers a more robust and familiar sense of who you are. Your blog posts will also be highlighted in Google search results, for your social connections to see
How To Get Started
You must already have a Google+ profile. If you don’t have a Google+ account, you can create one here first, before you continue with the steps below. If you already have a Google+ account, follow the steps below:
Log in to your Blogger blog
Tick the “I have read the above and fully understand ……” box
Click the “Switch Now” button.
Sign in to Blogger dashboard
Go to “Settings“
Click on “Posts, Comments and Sharing“
Scroll down to “Share to Google+“
Select your Google+ profile and click on “Save Settings“
Upon switching to your Google+ profile, your posts and comments will link to your public Google+ profile More so, your Blogger profile will become unavailable for visitors, and everyone will be redirected to your Google+ profile.
Feel free to check out this Google Plus Manual.