How to add Facebook like button below post? (CLASSIC TEMPLATE)

Step 1:

Go to Blogger Dashboard > Template > Edit Template HTML

Find the code as shown below:
*you can hold Ctrl+F to find it

<$BlogItemBody$> 

Step 2:

Paste Facebook like button code below the code above.

Facebook Like Button Code (2 Options):

With face:
<iframe src="http://www.facebook.com/plugins/like.php?href=<$BlogItemPermalinkURL$>&send=true&layout=standard&width=450&show_faces=true&action=like&colorscheme=light&font&height=80" scrolling="no" frameborder="0" style="border:none; overflow:hidden; width:450px; height:80px;" allowTransparency="true"></iframe>

Without face:
<iframe src="http://www.facebook.com/plugins/like.php?href=<$BlogItemPermalinkURL$>&send=true&layout=standard&width=450&show_faces=false&action=like&colorscheme=light&font&height=80" scrolling="no" frameborder="0" style="border:none; overflow:hidden; width:450px; height:30px;" allowTransparency="true"></iframe>