How can I propagate my Sansevierias?

Sansevierias, (san-se-VAY-ria, alternatively, -veeria, -vairia) hereafter Sans, are warm weather plants, often resting in the short days of winter. The most widely seen Sans, S. trifasciata, is also called Mother-in-Law tongue, Bowstring Hemp, Snake Plant. Reputed to be a favorite food of elephants, Sans come from warm, dry climates where the temperatures rarely go below 50 degrees F [10C]. Between 50 and 100 species are recognized in nature, in cultivation the varieties are numbered in the hundreds. The cultivars with colored margins, S. trifasciata 'Laurentii' for instance, can be grown from leaf cuttings, but the colored margin will not be present in the resulting plants. For these varieties, it is necessary to use root division for propagation.
To grow a new Sans, it will be necessary to take a fully grown leaf and cut it into pieces about 3-6 inches long [8-15cm], keeping careful track as to which end was closer to the root. These should be placed in a warm airy location to heal for a few days.
When planting the leaf-parts, use well draining succulent type soil, moistening it slightly. Several leaves can be put into each small pot, making sure to bury the root-end of the leaf. Planting them upside down is wasted effort as they will not root. Keep the pots out of full sun but in bright, indirect light until roots form. Kept at 70F [20C], roots should form in 4-6 weeks, depending on the species, lighting conditions, etc. Until roots form, water sparingly. When the first leaves emerge, they will not necessarily look like the parent plant. Some species of Sans have a juvenile form of leaf, with the mature form appearing later on the same plant.