If you telemarket, make sure you understand and follow federal law. There are certain activities you must avoid, including calling a consumer's residence before 8 a.m. or after 9 p.m.; calling consumers who have requested they not be called (telemarketers must keep "do not call" lists of people who have asked not to receive calls); withdrawing money from a consumer's checking account without express, verifiable authorization; or misrepresenting any information or lying to get a consumer to pay.