Auto expand comments and show Leave a Reply form?

How do I show a post’s current comments and the “Leave a Reply” entry box without the user having to click on the post name. I can see where many users would have no clue how to enter a comment and/or know that any comments are present. In a previous theme I used, adding the second line below in the index.php file fixed this, but it doesn’t work with the Vantage theme:

get_header(); ?>

<?php $withcomments = 1 ?>