<a href="http://twitter.com/share" data-url="<?php the_permalink(); ?>" data-text="<?php the_title(); ?>" data-count="horizontal" data-via="heyimjuani">Tweet</a><script type="text/javascript" src="http://platform.twitter.com/widgets.js"></script>

Code above belongs to the tweet button. Don’t forget to change the data-via attribute! Keep reading