Lay it all out on the table and let people assemble, roll, and eat. It doesn't have to be a neat restaurant-style handroll roll. Just roll it up like a burrito and enjoy with wasabi and soy sauce and some sushi ginger if you like. :)
Alternatively, you can just make easy rice bowls with all the ingredients and either omit the nori or tear it up in small pieces and sprinkle it on top.