How can I ensure successful propagation of bougainvillea plants?

To ensure successful propagation of bougainvillea plants, you can take stem cuttings from a healthy plant, dip them in rooting hormone, and plant them in well-draining soil. Keep the cuttings in a warm, humid environment with indirect sunlight until roots develop. Water the cuttings regularly and transplant them into larger pots or the garden once they have established roots.