Examine your philodendron carefully for old or damaged sections. Look for vine sections that are sparsely leafed and lanky. Cut these sections back to vigorous, heavily leafed growth. Make cuts above the swollen sections where leaves are growing.
Cut multiple vines back until each section is roughly the same length as the others. Adjust section lengths based on growing habit. Plants that are trained to climb might benefit from a more irregular trim than plants that are trained to hang over their pots. Cut excess leaders back to the soil.
Repot the plant if it has not been repotted in at least a year. Water and fertilize with a balanced fertilizer to encourage new leaf formation and promote vigorous growth.