How do I correctly load user_profile_form() to use in my theme?
Here is the code you need to follow:-

function THENAME_theme(&amp;$existing, $type, $theme, $path) {

return array(
    'edit_profile_user_profile_form' =&gt; array(
        'arguments' =&gt; array('form' =&gt; NULL),
        'template' =&gt; 'templates/edit/user-profile',
        'render element' =&gt; 'form',
        ),
);
}


Next thing You need to create a file called user-profile.tpl.php and save it in template folder.

In the user-profile.tpl.php file, write the following code to print out the fields:

&lt;?php print drupal_render($form['field_NAME_OF_FIELD']); ?&gt;