Simplify collaboration

When I invite a collaborator, they receive a link. Problem is that it sends them to a login page and they don't know what to do (nothing is explained). It would be preferable if the 'invite' button would allow them to make changes without registering (like https://webwhiteboard.com) Alternatively, perhaps after clicking the 'accept invitation' button, then perhaps they can be taken to a page explaining to them that they now need to create a new account in order to be able to make edits