Just take off the dead blooms or the seed pods with a fine pair of scissors. Whenever you feel like it. Feed them too, so they keep flowering. A bit of liquid feed every couple of weeks. If you want cuttings. Choose a shoot with no flowers or remove them/ or buds. About 5 inches long. Remove the lower leaves and trim to just below a notch. Little pot, bit of compost, pop in round edge, clear plastic bag cover, cool shady place. Wait a while. Roots through holes or firmly fixed and.... done.