Adding Pagination

Hello,

I am very new to WordPress and basically all I want to do is add pagination to this page: http://www.andrew-reynolds.com/ar_wordpress/?page_id=11

I have created a new template for this page and I am using custom post types to output the testimonials, but there are a lot more to add and I need the page paginated.

The current code for the template page looks like this:

<?php
/**
 * Template Name: Testimonial
 *
 */

get_header(); ?>
<hr class="slider">

<?php get_template_part( 'content', 'slider' ); ?>

<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
<section class="main_content">
    <div class="container">
        <div class="entry_box sitemap">
            <?php the_content(); ?>

			<?php endwhile ; else:  ?>
				<p>There are no posts or pages here</p>
			<?php endif; ?>

            <!--Outputs the testimonials-->
			<?php get_template_part( 'content', 'testimonials' ); ?>
        </div>
		<?php include('sidebar.php'); ?>
	</div>

</section>
<?php get_footer(); ?>

I have been reading http://www.andrew-reynolds.com/ar_wordpress/?page_id=11 but I am unclear where to place the code (within the template page, functions.php or within the custom post types).

As I say I am very novice and built this theme using Treehouse tutorials, any help would be greatly appreciated.

Thanks, Sam.