1. To add a new registration, you have to be first on your admin account.
2. Press on the Event tab ( ) from the menu.
3. Then press on the List tab from below.
4. Then press on the registration form from the Registration column of an event.
5. Here you will have to fill the required fields in order to add a registration. After filling the fields, press on the Register button in order to register a pending invitation to a user for the event.