"Oklahoma law makes it a misdemeanor to either pretend or profess to tell fortunes for a charge or to receive any gift or donation. The maximum punishment for fortune telling is six months in jail and a $500 fine. At least one other person has been prosecuted in Oklahoma County since 1992, records show."
It is rare for anyone to be prosecuted. A woman was charged and convicted last year, but she was scamming by charging $60 for a six-minute reading and other offenses.
It's always a good idea to check out your state laws and regulations before embarking on a tarot reading career. Tarot can be used for non-fortune-telling applications, such as counseling and advice.