Fermentation: Let it ferment for a few days in a warm place (room temperature - circa 20C). Taste the beer every day to see if it still taste unpleasantly of sugar. Mine have taken anywhere from two days to a week - it really depends on the yeast and on the room temperature, how long this will take. If the ginger taste is a bit weak, just add in more ginger.
Because this is a brewed ginger beer, it is important that the beer sits somewhere warm while brewing otherwise it will take quite a long time to work though the sugar. Make sure to use plastic bottles - glass bottles are quite likely to shatter because if the pressure build up under the carbonation process.