Register your phone number on the National Do Not Call Registry at donotcall.gov
Call 1-888-382-1222 from the phone number you want to register
Verify your number through the confirmation email if prompted
Keep your registration active; it does not expire
Report unwanted telemarketing calls to the FTC at reportfraud.ftc.gov
Ask individual callers to remove your number from their calling list
Check whether your state has its own Do Not Call list and register there if available