Salvia can be chewed as fresh leaves, or users can drink the extracted juices, or smoke the dried leaves as a joint. It can be consumed in water pipes or vaporized and inhaled as well.
Salvia is currently illegal in 23 states in the US. Salvia is regulated as controlled substance since 2006 in most states.
In California, for instance, where Miley Cyrus allegedly used the herb, the law prohibits selling to anyone under 18 years old. Cyrus had already turned 18 when the alleged incident occurred.
Salvia is widely sold online and in smoke shops, head shops, tobacco shops, and even gas-stations. 2 grams of extracted salvia runs around $40.