For example, there is a song that says He was warm, he came around like he was dignified. Instead of warm, you write cool then cross it out so that the students will understand it is something different or the opposite. Instead of around, you write a+ and draw a circle, instead of dignified, you draw a man digging, a leg with a circle over the knee and also write -fied. It's a little complicated and it requires some ability for drawing, but it's very memorable and the students enjoy trying to figure out what the drawings and symbols mean. They listen to the song to check their ideas and get the correct answers.
After the activity, they can sing the song together or write their own puzzles for the other students to try to figure out what they mean.