Whether you transplant small 'Black' hens and chicks (Sempervivum 'Black') -- hardy from U.S. Department of Agriculture plant hardiness zones 4 through 9 -- or a larger succulent such as a prickly pear cactus (Opuntia spp.) -- hardy from USDA zones 3b through 11, the keys to success lie in proper soil with good drainage. Therefore, you'll probably spend more time preparing the new growing area than you will transplanting your succulents. Also check each succulent's light requirements before you transplant because a succulent variety may need full sun or shade.
Many types of succulents exist, and what makes a plant a succulent is its ability to draw and store water in its tissues. Succulents also don't tolerate having wet roots, however. So the transplant location you choose for them should have good drainage. Avoid transplanting succulents to low spots.
Check a site's drainage by digging a hole in it when its topsoil is moist. Make the hole 12 inches in diameter and 12 inches deep. Fill the hole with water, and monitor its drainage. If water drains from the hole in fewer than three hours, then the soil has good drainage. If it takes three to 12 hours to drain, then the drainage is OK for most landscaping plants, but you still could improve the drainage. A hole that takes more than 12 hours to drain means the soil has poor drainage that definitely needs to be improved.
Fix Drainage in a Dry Climate
If you live in a dry climate, one way to improve soil drainage is to add a layer of gravel in the bottom of your desired planting area. Dig about 2 feet deep in the entire planting area. Place a 12-inch-thick layer of gravel in the excavated site, and follow it with a few inches of the soil you removed while digging. Over the top of the soil, place 6 to 8 inches of sharp sand. Afterward, the site will offer good drainage for succulents such as prickly pear.
Fix Drainage in a Wet Climate
If you live in a wet climate, create good drainage with an elevated "rock garden." On top of the current soil, set a layer of large, 8- to 12-inch-high rocks. Add coarse sand or pea gravel on the rocks, and then wet the site. Allow it to dry for a few days. Finally, add 3 to 4 inches of scree. A scree suggested by Urban Horticulture Program Assistant John McLaughlin, Ph.D., in an article on the University of Florida IFAS Extension website is a mixture that is 1 part Canadian sphagnum peat, 1 part potting soil, 2 parts course sand and 6 parts bonsai or poultry grit, which is small pebbles of porous granite or other stone. Mix the scree ingredients in a wheelbarrow, and then dump the mixture on top of the sand or pea gravel. Spread the scree evenly across the pile's top. Then cover it with a 1-inch-thick layer of 1/2-inch gravel.
The temperature at transplanting time should be at least 70 degrees Fahrenheit and not lower than 50 F, especially if you transplant small succulents. Wear a pair of thick, leather work gloves to avoid injuries from succulents' prickly points.
If a succulent you want to transplant is in the ground, then use a trowel or shovel to loosen the soil, sand or gravel several inches from the plant's perimeter, and gently remove the plant from the ground. Lightly brush soil from the roots.
Dig into the new planting site's soil material, making a hole deep and wide enough for the root spread of the succulent you want to put in the hole. Place the root part of the plant in the hole, and allow the fleshy or stem parts of the plant to remain above the soil line. Spread the roots, and cover them with the site's soil material, making the material even with the surrounding ground's surface. Tamp the soil. Allow the plant to dry out and to repair its roots for about one week before watering. Add water once each week thereafter. It's time to water when you stick your finger a few inches into the surrounding soil and find the soil is dry.