How to Display related posts in WordPress without Plugin :
WordPress Related Posts : According to Google's Matt Cutts, related posts will help the search bits to discover in depth content.More over ,they will help to increase page views in your website,which is better sign for SEO ranking.
Some dozen of WordPress plugins available for related posts,but they will slow down your website.so avoid using many plugins.
Paste the following code in your WordPress theme's single.php file
Go to Appearances >Editor >Single.php.
Here's the code to add WordPress related posts without plugin.
<?php
//for use in the loop, list 5 post titles related to first tag on current post
$tags = wp_get_post_tags($post->ID);
if ($tags) {
echo 'Related Posts';
$first_tag = $tags[0]->term_id;
$args=array(
'tag__in' => array($first_tag),
'post__not_in' => array($post->ID),
'posts_per_page'=>5,
'caller_get_posts'=>1
);
$my_query = new WP_Query($args);
if( $my_query->have_posts() ) {
while ($my_query->have_posts()) : $my_query->the_post(); ?>
<a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title_attribute(); ?>"><?php the_title(); ?></a>
<?php
endwhile;
}
wp_reset_query();
}
?>( Source )
Further advanced methods to add WordPress related posts :
1.Add related posts with thumbnails for WordPress
2.Display related posts in WordPress by category.
YARPP is the best WordPress related posts plugin :
If you are great techie, just install Yet Another Related Posts Plugin (YARPP) which do your work easier.Display a list of related entries on your site and feeds based on algorithm. Now this YARPP plugin having in built support to show related posts with thumbnail.
For Genesis Users :
1.show genesis related posts with thumbnails.