Roll out the gingerbread dough on a lightly floured surface and cut out shapes using a set of Christmas scene cutters. You'll need 2 sleigh sides, 2 sleigh ends, 2 reindeer bodies and 4 pairs of legs, 1 snowman with base and 1 tree with base. Place the pieces on large greased baking sheets, spacing them slightly apart.
Bake in a preheated oven, 180°C (350°F), Gas Mark 4, for 15 minutes or until the dough has risen slightly and is darkening at the edges. Leave for 5 minutes, then transfer to wire racks to cool.
Put the royal icing in a pastry bag fitted with a plain nozzle. Knead the red ready-to-roll icing until slightly softened, roll out thinly and cut out 4 top sections for the sleigh sides using the same cutter as before. Attach using piped royal icing. Roll out the black icing and cut out small squares for the reindeers' hooves. Shape and secure small red reindeer noses and a red scarf and black hat for the snowman.
Pipe royal icing decorations on the sleigh, reindeer, snowman and tree. Leave to set for at least 1 hour.
Assemble the scene by slotting the pieces together. Place on a board and dust lightly with icing sugar.