You've been told how already. See Answer 3.
OK, so think about it. How will you approach finding out what the problem is? Exactly how are your commands encoded into two bytes?
When you say 'Toys OFF', what exactly does incomingByte contain? In fact, do this: send each command in turn, and write down what incomingByte and incomingByte1 contain each time. By observing what incomingByte contains for each command, you will then see what response the code will give for each command.
Think it through, step by step. Write the result of every step down as you work through the code. This will shine a light on why it isn't behaving as you want it to.