Add Pagination in custom loop

source : How to fix pagination for custom loops?

<?php 
$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
$args=array(
   'post_type' => 'gadget',
   'post_status' => 'publish',
   'posts_per_page' => 24,
   'paged' => $paged
);

$temp = $wp_query;
$fp_query = null;
$fp_query = new WP_Query($args);

if ( $fp_query->have_posts() ) : while ( $fp_query->have_posts() ) : $fp_query->the_post();   

/* DO STUFF IN THE LOOP */

endwhile; endif;

next_posts_link();
previous_posts_link();

$fp_query = null;
$fp_query = $temp;
wp_reset_query(); ?>