Add numbered pagination to custom post type

I have a custom post type called Testimonials. I am using this code to display the testimonials – there are over 70 of them:

<?php
if ( is_page( 2628 ) ) { ?>
<div class="testimonial-page">
<?php 

//Define your custom post type name in the arguments

$args = array('post_type' => 'testimonials');

//Define the loop based on arguments

$loop = new WP_Query( $args );

//Display the contents

while ( $loop->have_posts() ) : $loop->the_post();
?>

<div class="headshot-row"><img src="<?php the_field('headshot'); ?>"><blockquote><?php the_field('excerpt'); ?></blockquote></div>
<div style="clear:both;"></div>
<?php the_field('testimonial_content'); ?>
<p><span class="name">&mdash;<?php the_field('name'); ?><?php if (get_field('business_and_website') && get_field('business_and_website') != "") { echo ","; } ?></span> <span class="biz"><?php the_field('business_and_website'); ?></span>
<hr>

<?php endwhile;?>
</div>

<?php } ?>

Only 10 are being displayed, and I need to add numbered pagination, like the pagination on the blog page. How can I add it here? Thanks so much.