The quick way to start is to create a frontend CRUD with the task
./symfony doctrine:generate-crud ie.
./symfony doctrine:generate-crud frontend user sfGuardUser
(or you can just generate the profile form with the doctrine:build-forms task)
From here you can customize the form. The most tricky part will be merging the two forms,
the sf_gurd_user_form (the one with the password and the username) and the sf_guard_profile_form. If you want profile fields and user fields on the same form you should use embedded forms as stated here:
http://www.blogs.uni-osnabrueck.de/rotapken/2009/03/13/symfony-merge-embedded-form/comment-page-1/
A snippet from that blog page:
class sfGuardUserForm extends BasesfGuardUserForm
{
public function configure()
{
parent::configure();
$profileForm = new UserProfileForm($this->object->Profile);
unset ($profileForm['id'], $profileForm['sf_guard_user_id']);
$this->embedForm("profile", $profileForm);
}
}