Add a designer or surveyor. Freeze someone to stop them signing in for now (you can unfreeze them), or delete them when they have left for good. Nothing is emailed by the system: you get a one-time sign-in message to send them yourself, with a link to the latest staff guide already in it. They choose their own password the first time they sign in.
Add someone
Send this to them
This is the only time the one-time password is shown. Send it as a private message, not in a group chat.