Manual Insertion

In case of manual insertion, You need to add the below piece of code in single.php (in most WP themes),
<?php if(function_exists('get_related_posts_slider')) {get_related_posts_slider();} ?>
Now you can see the related posts appearing in a slider format at the location preferred by you.
As Shortcode support is available in Related Posts Slider, you can use the below shortcode anywhere in the post content to add the preview slider of related posts.

[rps]

You can customize the “Related Posts Slider” width, height, background and foreground colors, font size etc. from the plugin settings panel.