Question
I have a potted fig tree that is about 5 feet tall.  It is a stick with three branches at the top and is now dormant on my unheated sunporch.  I would like it to be bushier.  When and how much do I prune it?
Thanks

Answer
Before you prune, there are other things to consider to make it "bushier". Most important is bright light. Full sun on the south facing side, with nothing to block out the sun.
Water regularly during the growing season. Water less in the winter.
Soil should be well drained and fertile. Repot every two to three years, and add some slow release fertilizer to the soil when you freshen it. That will probably be all of the fertilizer you will need. Low nitrogen fertilizer is best for fruiting, for thick foliage, use high nitrogen.
Prune to shape in spring, or late winter just before new growth begins, but remember that the first crop is borne on last season's growth. Figs require very little pruning.
Make smooth clean cuts, close to the lateral branch, and do not leave any stubs. Prune to control the trees height by opening the bush, removing dead wood, and suckers from the trunk and main branches. this pruning method produces easier picking, larger fruit, and better control of the tree's vigor. Prune sufficiently to stimulate about a foot of new growth each year on most branches.