Add next/prev to single post in Genesis Framework.

functions.php

<?php

/* Add Previous & Next Links in Genesis Single Post Page
------------------------------------------------------------ */

add_action('genesis_after_post_content', 'genesis_post_navigation');
function genesis_post_navigation() {
if ( is_single ( ) ) { ?>

    <div id="prev-next">
      <div class="prev-link">&larr; Previous Post
        <?php previous_post_link('%link', '%title'); ?>
      </div>
      <div class="next-link">Next Post &rarr;
        <?php next_post_link('%link', '%title'); ?>
      </div>
    </div>
  
  <?php } 
}