I've already written my messages, I wrote the messages 3 times. First, "I will concentrate in my lesson." Another one is "I will exercise every day." Last, "I won't play games too much." Thanks for your advice, It's good for me.
I think, If she likes rock music and movies, you should buy her favorite rock music band CD and give the movies poster to her. Or you can take her to the rock concert or movies theater.