Go to Manage, then People, then press "Add staff". There are two ways to do it.
The quickest is to share a join code. Copy the code or link and send it to staff, put it in the staff bulletin, or show the QR code at a staff meeting. Anyone with it can join your school.
The other is to add people by email. Paste in a list of email addresses, or drop in a spreadsheet exported from SIMS, Arbor or Bromcom. Press Check, then "Add" to add them. We email each person to say you've added them, and they're in as soon as they sign in with that address.
Staff don't need a welcome email or a password. If someone says they can't get in, they're most likely signing in with a different email address from the one you added. Check the address on their People page and ask them to use that one.
People you've added show as "Not signed in yet" until they first sign in. You can still set them courses, add them to groups or remove them. To remind them, open People, choose "Not signed in yet" under Status, tick the people you want and press Remind. They're sent their invitation again, at most once a week.
To control who can use the join code, go to Settings, then Joining. You can make people wait for your approval, set the code to stop working after a date or a number of people, or press "Make a new code" to switch the old one off. People who have already joined keep their access.