You might want to check out books like The Ethical Slut and Opening Up: A Guide To Creating and Sustaining Open Relationship. They have a lot of good tips for talking about this kind of topic. Men, in my experience, are more likely to be bound up in cultural narratives about owning and controlling women and even if they don’t believe in that consciously, it’s in their subconscious. Talking about that and confronting it before you ever touch or even think about touching anyone else is a really advisable idea.