How secure MAMP Stack, etc., for localhost only use

After installing MAMP Stack, what security changes should I make for localhost use only - and to prevent access by anybody from elsewhere? And in particular:

1. Security settings for Apache https.
2. Admin password for MySQL and user password for same.
3. Ditto, phpMyAdmin.
4. Ditto PHP.
5. Ditto Drupal (after installing that module).
6. Ditto Moodle (after installing that module).

i'm quite concerned that immediately, after MAMP Stack is installed on a Mac, admin passwords seem to be defaults that are publicly known from the BitNami web site!