When you start a trial or subscription, you will receive all relevant information in an email that comes from Freemius. (Freemius is handling payments and licenses for us.)
If you later need to manage licenses, subscriptions and websites, you can do so
- on your WordPress admin dashboard, in the Account submenu under the Tag Groups menu.
- in your user account. There you also find a FAQ section that explains common operations, like moving the license to another website.