Trying to modify a menu with hook_menu_alter What is the best way to add a link to the user menu for a menu defined in my custom module?
Implement the hook_menu() in your custom module, then clear the cache and you will see the link in the User menu (you need place the block for the User menu in a region).

function YOUR_MODULE_NAME_menu() {
   $items = array();
   $items['/path'] = array(
   'type' =&gt; MENU_NORMAL_ITEM,
   'menu_name' =&gt; 'user-menu',
   'title' =&gt; t('Title'),
  );
  return $items;
}