When you receive a box of succulents, you should open it at once. Not that you will not! You will be eager to see the contents. The plants will need air and light immediately. Be careful not to let the light be too intense for a few days. Avoid putting them in direct sunlight. Remember that the plants are succulent. They have evolved to resist evaporation from leaves or bodies and will not wilt like ordinary plants. Light and air are more urgent, immediate considerations than water.
Put the plants in a warm, bright place for a day or two, and, if you wish, pot them up at once in well-draining potting soil. Light spraying now and then may help if the weather is hot and dry, but avoid this in cold or damp weather. Let the signs of new growth guide when to begin regular watering, based on weather conditions, plant size, and the type of plant.
Remember that cuttings without roots will not take up water. For cactus cuttings without roots, larger cacti have more reserves to draw on and are less likely to form roots as quickly as young, small ones. Therefore, it is wise to plant these rootless, larger plants in extremely porous, gritty soil that dries out within a few hours of watering. Or you can put a little water in the pot saucer now and again, which will be taken up into the soil in the lower half of the pot so that when roots form, they go down looking for that moisture. In the meantime, they are not sitting in soaking-wet soil and rotting.

For plants with roots, pot them in moist soil and watch for signs of life before starting a regular watering program.
Gradually move the plants or cuttings into the light they need, eventually into full sun. If you are not sure whether the plants need full sun, keep them in a very bright place, out of direct sunlight, until you find out what light each plant needs.
Source: theamateursdigest.com
Links
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus