Put the required amount of fumadil into a mayonnaise jar (or other
container) of very cold water.  Cap it and shake it up.  You can keep it
cold in the 'fridge or freezer for a while, then shake it up again, till
it's all dissolved completely.  Then just add it to the already mixed
sugar-water, which can be warm, and stir it all up.  The fumadil doesn't
mix well at all with anything but cooold water, IME.   I hope this is
helpful--J.