Approximately ½ hour before assembling the float, place your mug in the freezer and chill.Remove mug and pour about 3-4 ounces of root beer into the bottom of the mug.Add 1 scoop of ice cream.Pour another 2 ounces of root beer over the ice cream.Add another scoop of ice cream on top and then fill the mug to the top with the remaining root beer.