Make sure the fuchsia's soil is moist before you begin pruning.
Remove dead, damaged, spindly and crossing branches.
Cut weak, broken and frost-damaged twigs down to their main stem.
Prune upright branches to one-third to one-half of their summer size.
Cut the healthy side branches down to two or three nodes from the fuchsia’s central framework. (A node is the thicker portion of a stem or branch from which leaves formerly grew.) Make each cut above the node at a distance roughly equivalent to the diameter of the branch you’re cutting. At the end of this process, each branch should have no more than three new leaf buds. While pruning the side branches, train the fuchsia into your preferred shape. Typically, you’ll want your fuchsia to have an even, nicely rounded shape that will maintain a good balance of lateral growth at the top and bottom.
Remove old leaves to prevent insect pests and other problems from affecting new growth. Spray the fuchsia with a dormant spray, if desired.