A single leopard gecko should be kept in a screen-lidded lizard terrarium no smaller than 10 gallons, and 5 gallons should be added for each additional gecko kept in the same habitat. It's okay to house two or three leopard geckos together, though no more than one male should be kept in the same space. (They tend to fight over territory.)
Be sure to give each leopard gecko two or three rocks or pieces of wood that can be used as hiding spots. Though the terrarium should generally be kept dry, add a layer of peat moss to one hiding place and mist it daily to provide a moist refuge.
Maintain a daytime temperature between 75-85º F (24-29º C) and a nighttime temperature between 65-75º F (18-24º C), using an under-tank heater if necessary. If you do use a heater, get a thermometer for both the warm end and cool end of the terrarium to be certain that the entire habitat stays within the recommended temperature range.
Line your leopard gecko's home with reptile carpet until it measures 6 inches or longer. When the lizard reaches adulthood (longer than 6 inches), line the terrarium with a 2- or 3-inch layer of calcium sand. Maintain a clean habitat by removing waste weekly and changing bedding at least once each month.