How do I arrange cover for an absent staff member?

Go to Skills → Find cover, pick who’s absent and the day. You’ll see who can cover (ranked by matching skills) and the exact sessions that need covering. Click “Assign as cover” next to a person — their sessions for that day are handed to the cover, who sees them on their staff-app schedule with a “Cover” badge (and gets a notification if they use the app). The timetable itself is untouched, and you can undo the arrangement anytime.