The manual registration of companions is done via the "Guests" menu:

1. Select the guest or guests to whom a companion should be added.
   
2. Go to the end of the guest list and select "Register and add companion" from the "Choose action" dropdown, then click the "Apply to selected" button.
   
3. An anonymous companion will now be added to the guests, whose details can be edited just like those of the main guest. Simply click on "(+1)" next to the main guest and follow the link "Companion of First Name Last Name" to edit the companion's details.
   
4. If you want to send the main guest an updated registration confirmation, you can also do this via the "Choose action" dropdown (at the end of the guest list). Select "Send mailing" and choose the "Registration with companion" mailing in the desired language, then confirm by clicking the "Apply to selected" button again. Alternatively, you can send the registration confirmation via the "Mailings" menu.