How to Add a Facebook Share Button to your Blog Posts

Click Here then goto Blogger Dashboard>> Design>> Edit HTML 
Then...

1. Save Your Template by clicking Download Full Template
2. Check the Expand Widget Template box
3. Search your template code for this (< div class='post-header-line-1'/>) or ()
4. Paste the button code you got from Here directly under the code snippets in step 3
5. Click Save and your done :)

*Note: Be sure to line up the beginning of the button code(< a name=) with the beginning of the code snippets talked about in step 3.