Here's an example:
For the parent who is tired and does not feel like playing with her five-year-old child, the encoding process is--
PARENT - Tired - (Encoding process) = (Code) "I am tired"
But if this parent selects a code that is "you" - oriented, she would not be coding her "feeling tired" accurately:
CHILD - Parent being Tired - (Encoding process) = (Code) "You are being a pest"
"You are being a pest" is a very poor code for the parent's tired feeling. A code that is clear and accurate would always be an I-Message: "I am tired," "I don't feel up to playing," "I want to rest." This communicates the feeling the parent is experiencing. A You-Message code does not send the feeling. It refers much more to the child than to the parent. A You-Message is child-oriented, not parent-oriented.
Remember to always use I-Messages!
*Excerpt from Dr. Gordon's book, Parent Effectiveness Training, P.E.T.