create link in admin menu

In the settings, you can specify the URL of a help page.

If you need to add more links, you can use hook_domainadminlinks in a custom module:

Here is an example:

function mymodule_domainadminlinks() {
   $links = array();
   global $_domain;
   
   if (user_access('administer domain blocks')) {	               
     //Changing sidebar blocks
     $links['domadm_region'] = array(
       'title' => t('Edit page regions'),
       'href' => 'admin/build/domain/blocks/'. $_domain['domain_id'],
       'weight' => -4,
     ); 
     //Add new sidebar block    
     $links['domadm_block'] = array(
       'title' => t('Add region block'),
       'href' => 'admin/build/domain/blocks/add',
       'weight' => -3,
     );              
   }	
   return $links;
  
}