Hi,
Custom order fields will be included in the email to the administrator automatically.
For the email sent to the user, you will have to edit the "order creation notification" email via the menu System->Emails and add the code below in it if you want the user to also have the information in his email :
$fieldsClass = hikashop::get('class.field');
$fields = $fieldsClass->getFields('frontcomp',$data,'order','');
foreach($fields as $fieldName => $oneExtraField) {
echo "\r\n".$fieldsClass->trans($oneExtraField->field_realname).' : '.$fieldsClass->show($oneExtraField,$data->$fieldName);
}