My son was given a Jade Tree  recently  and it has lost all of its leaves because he was told that it needed minimal care.  He unfortunately  didn't do any reading up on the care for the plant.   It was in his room with very little light and perhaps wrong watering.    I have done some reading and it is now near a cool window and has been well watered / and drained well    twice now . It is in a south facing window so it is getting all available light but all of its leaves have fallen off..     So the question is  How do I care for it now that it has lost all of its leaves/    All help will be gratefully accepted   
Thanks

Warren
    

There are two ways jade leafs drop. If they dry out and fall it is more or less natural. The other way is that they have gotten too much water. Then they pump up leafs with as much water as possible before they drop it. The leaf is like a baloon. That is most likelly your issue since it is winter time in nortern hemisphere.

What you need to do now is stop watering until you see new growth coming in spring.