Doing a scene means acting out a fantasy. He might want you to spank him, tie him up, play the cruel school teacher, or whatever.

Except as a boon to him, you almost never do the scene exactly as he describes. First, it is not good style. If you are following his directions, it seems like he is in charge. If that doesn't bother either of you, fine. But many submissives will not like the feeling of being in control. And following his scene does not encourage your sense of dominance.

There are two very good reasons to change the scene. One is if it isn't good for him. You are in charge. If you decide the scene isn't good for his self-esteem, change it so that it is. Or don't do the scene.

The other reason for changing his scene is so that you can enjoy it too. Take parts of his scene that you like and add ideas that you like. If you can't change it to something you want to do, then don't do it. Most people are turned off by at least one scene. Most women do not like crossdressing or pain.