Avoid overwatering your succulents to avoid having to propagate them. This is difficult to generalize as each species has a different response. The roots of succulents grown in water are also more adapted to absorbing oxygen from their aquatic environment rather than a terrestrial one, so there will be a transitional period of root development once you move the plants into the soil. Once you've chosen the ideal location for your cuttings you can just relax and wait for them to grow. With leaf cuttings, roots will begin to grow out of the base. A new baby plant will then emerge.