join table with query posts

hello,
and i have table called
userbookmark
contants fields
1-id
2- user_id
3- post_id

and i have bookmark system
when user press bookmark it goona insert these infos
1-id ( autoinc..)
2- user_id ( 1 for example )
3- post_id ( 1 for example )

and i want make query to show bookmared posts with table above i just want to make join but i don’t know how in wordpress

i have this query

<?php
	 $args = array(
				   'cat' => '1',
				   'author' => '1',
				   'post_type' => 'post',
				   'posts_per_page' => 6,
				   'paged' => ( get_query_var('paged') ? get_query_var('paged') : 1),
				   );

	query_posts($args);

while (have_posts()) : the_post();
 /* Do whatever you want to do for every page... */
?>
	<a href=""><?php the_title();?></a><br />

      <?php

endwhile;
?>

please please help me