One way to do that? Making a yes/no/maybe list. Since “rough sex” can mean, like, a bajillion different things, you have to figure out what rough things you actually want to try!
It may not need to be said, but there’s a H-U-G-E difference between having a partner push you up against a wall and pound you hard and deep and having your partner tie you to a bed and whip you until your welts say their name. Identifying and establishing limits is key