Educating yourself about how to care for your first snake is quite an experience, and a necessary one if you are going to provide for the health and care of your snake. Before you bring a snake into your home, you should consider how large it will grow, and what its habitat requires in terms of size of cage, lighting, temperature, and humidity.
With reference to cage size, most snakes can be classified into three groups. Garter snakes and grass snakes can be kept comfortably in a 10-gallon or 20-gallon aquarium. King snakes, rat snakes, milk snakes, gopher snakes and other colubrids (belonging to the zoological family Colubridae) will be happy in 30-55 gallon tanks. Boa constrictors and pythons are a different story. Most adult boas and pythons range from 18 inches long to a world-record 32 feet long. Some weigh more than 500 pounds. With these large pets, custom cages are needed. If you are talented in the industrial arts, consider building your own cage with materials like plywood or melamine (a crystalline powder used to make high density resins used especially for molded plastics). If you don't want to build your snake's home, custom cages and kits are readily available.
For lighting and heating purposes, your best option is buying a full-spectrum fluorescent bulb for vitamin and mineral metabolism. An incandescent bulb can be added to the same fixture in the cage top to provide both light and heat. Remember that the higher the wattage, the higher the temperature.
For almost all herps, including snakes, it is necessary to provide the optimal temperature, as well as a temperature gradient so the snake can go to that area in which he feels most comfortable. To accomplish this, both a primary and secondary heat source are necessary.
Primary heat source: A primary heat source is necessary to keep the temperature of the entire cage within the proper range. A series of incandescent lights over the cage is one of the best heat sources. At night, these lights will need to be turned off and another heat source may be needed depending on the ambient temperature. A heating pad placed under the cage, ceramic infrared heat emitters or panels, or more expensive nocturnal reptile incandescent light bulbs which produce heat, but little visible light, can be used. For larger enclosures, a space heater or separate room thermostat can be used to keep the room at the appropriate temperature. Fire alarms should be placed in rooms where lights or other heat sources are used.
Secondary heat source: A secondary heat source creates more heat in specific areas of the cage to provide a temperature gradient. To best supply this gradient, the secondary heat source should cover only 25-30% of the surface of the enclosure. The secondary heat source could be a 50-75 watt incandescent bulb in a ceramic base, securely mounted where the animal can not touch it. There are also special 'basking lights' available. Either type of light should shine down on a particular basking area from outside the cage. An under-the-tank heater (placed at one end of the tank only, thus creating a cool side and a warm side) is another option. DO NOT USE HOT ROCKS AS HEAT SOURCES. THEY CAN CAUSE SEVERE BURNS.
Humidity is another key consideration when creating your snake's habitat. Each species has a different humidity requirement. Consult books, magazines, and reliable Internet sources to learn about the needs of your particular snake. If your snake needs a particular humidity, obtain a humidity gauge and the appropriate misting or fogging equipment.