Fill a plastic seed tray with a well-drained, lightweight rooting mixture such as half sand and half perlite or vermiculite. Moisten the rooting mixture with a spray bottle until it is moist clear through but not dripping.
Cut several stems 1 1/2 to 2 inches long from a healthy princess plant. Make each cut just above a leaf or bud with pruners or a sharp knife.
Pinch the leaves from the bottom half to two-thirds of the princess plant stems. Dip the end of the stems in rooting hormone.
Make a planting hole in the center of each cell with your finger, and plant each cutting in a hole with the lowest leaves just above the surface of the soil. Pat the rooting mixture around the stems.
Slide the tray into a clear plastic bag and close it with a twist tie or rubber band. The plastic creates a warm, greenhouse-type environment that keeps the rooting mixture moist for several weeks. Open the bag for 10 minutes twice a week to provide air circulation and prevent rot.
Remove the bag when the cuttings show healthy new growth, usually within three to six weeks. Plant each rooted cutting in a 3- to 4-inch pot filled with commercial potting soil.
Place the pots in bright, indirect sunlight. Water as needed to keep the soil moist; never let the soil become bone-dry or dripping wet.
Fertilize the young princess plants once every month with a water-soluble fertilizer mixed at a rate of 1/2 teaspoon in 1 gallon of water.
Pinch the tips of the stems once or twice to create full, bushy plants. Allow the plants to mature until the weather warms in spring, and plant them outdoors. Alternatively, plant the small shrubs in one-gallon containers and allow them to mature for an extra year before moving them outdoors.