Most Christmas cacti that you buy are started with four or five leaves at the base. If you want to divide it you should be able to do it that way. Sadly, a lot of the roots will most likely be damaged and you should give it less light and less water for a few days to let it recover from the shock. Alternatively you can take clippings of the leaves (hopefully at least two segments) and start them that way. Good luck! Ryan
If you decide to divide it now by splitting up the rootball and not by way of leaf cuttings, the sections most likely won't flower for you until next year since they don't like to be disturbed especially at this time of year when they are close to setting buds in the months of Oct-Nov.
great thanks didn't think about that if I decided to divide I will wait till after it is done flowering.Thanks for the advice.