How does it work?

1. Select the collaborator field from the list of field types
2. To add more collaborators to the record, enable the option - Allow adding multiple collaborators. 
3. To notify the collaborator, enable the option - Notify the user when they are added to a record.

By default, both of these options are disabled.

Non-collaborator

If the collaborator doesn't have access to the base, their name will not appear in the dropdown list. In that case, you can straight away type their email address and hit enter.

It takes you to the page to add them to the base.

(or)

In the drop-down list of the collaborator field, click the + Add collaborator option and add them to the base.