You may want to add a like button to your blog (look up).. here's how you do it.
Click layout, add new gadget, html/javascript
paste this:
<div class="fb-like" data-href="http://yourblogname.blogspot.com/" data-send="true" data-layout="button_count" data-width="450" data-show-faces="true"></div>
and click save.
Make sure to change the link to your blog!
Somewhere on your blog put this html:
<div id="fb-root"></div>
<script>(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_US/all.js#xfbml=1";
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));</script>
