Think about it: 
Backtalk is addictive, so it must be handled as a serious offense. A child who talks rudely to a parent once or twice and gets away with it will continue the behavior, and it will progressively get worse. Most children will attempt backtalk at some point. When a parent responds calmly and with authority, the behavior will stop.  

Announce your expectations:
If a child has developed a habit of backtalk, it will take firm action to stop the behavior. Have a meeting with your child to announce that backtalk will no longer be tolerated. Decide on a series of consequences that will occur each time backtalk occurs. Consequences may involve losing a privilege, such as telephone use, television watching, or visits with friends. They may be an additional chore, or an earlier bedtime. Then announce the sequence in which the consequences will occur. “When you talk back in a disrespectful way, you will lose your telephone privileges for the day. The second offense will cause you to lose your TV show for the night. The third will…” Each day will start with a clean slate. After the meeting, calmly and firmly follow through.

Don't empower it:
Whenever a child talks back, immediately stop the conversation and walk out of the room or walk away from the child. If the child follows you, calmly and firmly announce that you will not tolerate disrespect, then pointedly ignore the child. Later, when you have calmed down, let your child know what the consequence will be for the backtalk.
 
Use a quarter-board: 
Tape your child's allowance, in quarters, to a piece of cardboard. Tell your child that each time he talks back to you, he will lose a quarter from his allowance as a fine. He'll get what's left at the end of the week. If your child uses up all the quarters, add a chore or eliminate a privilege for each offense (or continue taking quarters from the next week). Start fresh with each new week. This series of events is meant to be a temporary training situation. When the problem seems under control, let your child know that you appreciate his efforts to control the backtalk, and that you'll no longer be charging the fine. However, make it clear that if the behavior ever becomes a problem again, you'd be happy to head to the bank for a roll of quarters.
 
Teach: 
If a normally respectful child makes a disrespectful comment, look him in the eye and make a serious, firm comment such as, “That is backtalk and is not allowed in this family.” Continue the conversation as if the backtalk did not occur, expecting the child to comply with your request. Do not empower the backtalk by arguing over the issue that triggered it.