Cooking rota

Say you have three people, and sometimes they all eat together, and sometimes they eat together in each of the pairs. Say you want to keep track of whose turn it is to cook in each of these three configurations. Say you'd quite like some kind of physical method of doing this so it can be incremented in the kitchen. I'm thinking it must be possible with jars and beads, or some kind of abacus like thing, but I can't entirely pinpoint how best to do it. If it's something that it's easy to make a second copy of for keeping track of whose turn it is to buy dinner in the same groupings that would be awesome.

Any ideas?