How to Prune common winter cactus?
Cut the plant back in spring to encourage fuller growth. It will branch out and flowers will grow at the cut. Clean and sharp pruning shears are the best instruments for this to avoid ripping the stem.

common winter cactus · Schlumbergera truncata
Also known as: crab cactus; lobster cactus; Christmas cactus
False christmas cactus is known for its low-maintenance profile, thriving under bright, indirect light and requiring a well-draining soil mix. Special care points include avoiding overwatering by allowing the top inch of soil to dry out between waterings and facilitating a cooler environment during fall to promote blooming. Pruning after flowering helps maintain shape and encourages future blooms.
Cut the plant back in spring to encourage fuller growth. It will branch out and flowers will grow at the cut. Clean and sharp pruning shears are the best instruments for this to avoid ripping the stem.