Newsletter Plugin - Multiple "lists"

I'm getting very excited to try to the newsletter plugin that I bought, but realized there are no instructions for allowing multiple lists.

For example, one of our clients in which we are using phplist is a salon/spa.  They have separate lists for each provider (hair stylist, massage therapist, etc.).  Then, when a particular provider has an opening for a given day, they send a message to the subscribers of that list.  Each subscriber can also subscribe to multiple lists.  For example, I use a particular hair stylist and a particular massage therapist, so I subscribe to both of these lists, but I don't really care if someone else is available or has a special running because I don't use the other providers.

Most of our clients have this situation where they use multiple lists.  One of our clients has about 42 different lists that people can subscribe to and there are just checkboxes on the subscription page to show which lists they want to subscribe to.  They do forensic training and once you've taken a particular class, you really don't care about that class anymore, but you want to know when the advanced class will be taught, so you can change your subscription and remove yourself from the introductory course list and then add yourself to the advanced list.

Of course, when you go to send a message, you can select which list(s) the message will be sent to.

How do we setup multiple lists using the Newsletter plugin?