A large enough "cage" is very important for beardies. Aquarium tanks make good habitates. Juveniles under ten inches can manage in a 20gal. aquarium, but adult dragons should be housed in a 55-60 gal. tank.
It is essential for the tank to have a proper substrate (material lining the bottom). The best substrate is one that is inexpensive, absorbent, easily cleaned, and digestible if swallowed. Some appropriate substrate materials include paper towels, indoor/outdoor carpeting, and newspaper. Do not use cedar shavings, gravel, crushed corn cob, kitty litter, or wood shavings.
A screen top will allow adequate ventialtion and let humidity escape.
In their natural habitat, these dragons use rocks and limbs for basking and shedding their skin so it's important to duplicate this in captivity. Pieces of oak and rocks that are flat on one side work well.
Because reptiles are cold-blooded, they cannot regulate their own body temperatures. Bearded dragons need a temperature gradient in their environment. Enclosures should contain a basking area that is around 95-105 degrees F. The "cool" side of the tank should be between 75-85 degrees F. A thermometer in each area of the tank is recommended. Stick on types should be avoided, however, since they can be off by as much as 20 degrees. Accuracy is important! Do not let the temperature drop below 65 degrees F. DON'T USE HOT ROCKS AS SOURCES OF HEAT.
Lighting is another key element in the environment of bearded dragons. Dragons need a certain spectrum of ultraviolet (UV) light called UVB to make Vitamin D. The best source of this is natural sunlight. Dragons can be placed outside if it is warm enough, but don't use a glass cage. The glass traps the heat and the excessive temperatures can harm or even kill the dragons. Use a wire or screen cage and provide a shaded area in case the dragons get too hot.
The second best light source for UVB are special mercury or fluorescent tubes.
Clean their habitat on a regular basis with a mixture of bleach (10%) and water (90%). Make sure to thoroughly rinse the bleach mixture off. Anything sprayed with bleach must be completely free of bleach and bleach odors before the dragons are returned to their enclosure.
Remove feces daily.
Dragons can carry the salmonella bacteria so handwashing should be a ritual, BEFORE AND AFTER handling dragons and their cages.