How do I set up listening for https requests in apache2?

One of my virtual hosts has a form of:

```
    <VirtualHost *:80>
        ServerName central
        DocumentRoot /var/www4
        ...
    </VirtualHost>

```

How should I modify this extract of my virtual-host-config to enable apache to listen to https? I need it because my website is supposed to send https POST requests at login. I've tried changing the opening tag for:

```
    <VirtualHost *:80 *:443>

```

..., but it didn't work. Any ideas?