How do you undo a Rubik's Cube when there is one wrong square on 4 panels?

To undo a Rubik's Cube with one wrong square on four panels, you can use the "edge flipping" technique. First, identify the incorrect squares and make sure they are positioned correctly relative to each other. Then, perform a specific series of moves, such as the "sexy move" (R U R' U'), to manipulate the cube while keeping the other pieces intact. Repeat this until all squares are correctly aligned.