Lists are created in Mailchimp as a way of working out where registrations are coming from and create automations specifically for that group.
To create a new list in Mailchimp do the following:
1. In Mailchimp click List > Create List
2. Name the list with an appropriate identifier e.g. Voucher Offer Facebook
3. Default email address should be [email protected]
4. Default from name should be Beer Cartel
5. How people signed up to your list - choose reuse reminder from another list and choose Beer Cartel List
6. Click Save
7. If those registering are going to be interacting with forms or confirmation emails then you will need to edit the Signup Forms - to do this copy the settings/html settings for each form from Beer Cartel list.
This should then have created the new list. If required the List ID for this can be found by going Settings > List name and defaults > List ID. It should look something like this: 70ac0e2e1e.