Fill the planting container to the top with potting soil. Spray the soil thoroughly with water from the spray bottle to make it moist.
Select a stem for propagation in late spring or early summer. Use a healthy Satsuma orange plant or tree. Choose a stem that is current growth -- a month or two old. Do not use a very soft new stem or an older hard and woody stem. The ideal stem will be flexible and it will snap when you bend it. Cut a 6-inch stem off just below a leaf node with the pruning shears. Remove the bottom leaves from the stem to leave two or three leaves at the top of the stem. If the leaves are large, cut them in half -- this reduces moisture loss from the cutting.
Insert the prepared stem into the center of the container, pushing the stem two to three inches beneath the surface of the potting soil. Press the soil gently around the edges of the stem with your fingers to make the stem stand straight in the container.
Place the food bag over the stem in the container and secure the bag to the rim of the container with the rubber band. Place the container in a moderately warm location in indirect light.
Remove the plastic bag daily and mist the soil lightly with water to keep the rooting environment moist. Replace the bag each time and secure it with the rubber band.
Loosen the plastic bag after you notice new growth beginning on the stem cutting to allow fresh air to reach the cutting. Gradually decrease the humidity around the cutting every day by loosening the bag more until you eventually remove the bag completely -- over the course of several days.
Transplant the new Satsuma orange plant to a permanent growing location after the cutting is growing actively.