Using rooting hormone is a popular method of promoting root growth and increasing the chances of success when propagating houseplants. Rooting hormones contain a naturally occurring plant hormone called auxin, which stimulates cell division and growth, and encourages the development of roots. Here's a detailed description of how to use rooting hormone in houseplant propagation:

1. Select a healthy stem: Choose a healthy stem from the parent plant that is at least 4-6 inches long and has several leaves on it. Choose a stem that is free from disease or damage and is growing vigorously.

2. Prepare the cutting: Use a clean, sharp knife or scissors to cut the stem just below a node, which is where the leaf attaches to the stem. The cutting should be at least 4-6 inches long, and it should have at least one or two leaves attached to the top of the stem. Remove the leaves from the bottom one-third to one-half of the stem.

3. Dip the cutting in rooting hormone: Pour a small amount of rooting hormone into a shallow dish or container. Dip the bottom of the cutting into the rooting hormone, making sure that the cut end is completely coated.

4. Shake off the excess hormone: Gently tap the cutting to remove any excess rooting hormone.

5. Plant the cutting: Insert the bottom of the cutting into a rooting medium such as vermiculite, perlite, or water. Make sure that at least one node is covered by the rooting medium. Gently press the medium around the stem to hold it in place.

6. Provide the right environment: Place the container in a bright, warm location, but out of direct sunlight. Cover the cutting and container with a plastic bag or clear plastic wrap to create a humid environment. This will help the cutting to establish itself and promote root growth.

7. Wait for roots to grow: Roots should begin to grow in 2-4 weeks. You may notice small bumps or nodules appearing on the stem, which are the beginning of root growth.

8. Transplant the cutting: Once the roots are at least an inch long, you can transplant the cutting into soil. Choose a small pot with well-draining soil, and make a small hole in the center. Gently remove the cutting from the rooting medium, being careful not to damage the delicate roots. Place the cutting into the soil and gently press the soil around the stem.

9. Care for the new plant: Water the new plant thoroughly, and place it in a bright, warm location, but out of direct sunlight. Keep the soil evenly moist, but not waterlogged. With proper care, your new plant should grow and thrive!

Using rooting hormone can be an effective way to increase the success rate of houseplant propagation, particularly for plants that may be more difficult to propagate through other methods. However, it's important to use rooting hormone in moderation and to follow the manufacturer's instructions carefully to avoid damaging the cutting or the parent plant.