Add sugar in milk and cook stirring until it boils. Turn down the heat when it is boiled and wait until it cools down a bit. If you pour boiling milk on gullac, it will get mushy. If milk is too cool sheets will not absorb the milk. Therefore, you must find just the middle. Place one line gullac sheet on tray and soak it with a big spoon milk. The shiny parts of the sheets must be on top. Put roughly ground walnuts in the middle and line the rest of the sheets. Keep it in the fridge for 1 hour, then cut into slices and serve. Pour rosewater in the milk or on gullac when you are serving.