On the floor map, a table's colour is what tells you its state without reading anything. You choose those colours for your venue.
Owners and Managers only.
Venue Settings → Floor Plan.
You pick a colour for each of three states:
They're listed in that order deliberately: "who's actually here" is the reading most venues care about most during service.
You pick from a set of prepared colours rather than entering your own colour code. Each one is a matched set — the top of the table, both shaded sides, and the label — checked to stay readable in both light and dark mode.
That's a deliberate limit. A map is only useful if it can be read at a glance across a dark room, and a freely chosen colour can easily end up with a label you can't read at an angle. Picking from prepared sets means every combination works.
The preview shows real table blocks at the map's angle, with their shading, rather than flat colour squares — you're judging the thing you'll actually be looking at during service.
You don't have to. A venue that never opens the colour settings gets sensible defaults, and the map works exactly as it would otherwise.
There's no Floor Plan option in Venue Settings. Either the floor map isn't switched on for your venue, or your role isn't Owner or Manager.
Colours changed but the map looks the same. Confirm you're on the map rather than the table list, and that you saved your selection.