Install the plugin to WordPress
Open and edit template.php file
To enable incline editing add to container of field value:
<?php echo acf_content_editing('FIELD_NAME'); ?>Example:
<?php
$user_name = get_field( 'user_name' );
$message = get_field( 'message' );
?>
<div class="block-testmonials-item">
<div class="post-info">
<div class="middle-area">
<a class="name" href="#">
<b <?php echo acf_content_editing('user_name'); ?> >
<?php echo esc_html( $user_name ); ?>
</b>
</a>
</div>
</div>
<p <?php echo acf_content_editing('message'); ?>><?php echo esc_html( $message ); ?></p>
</div>