I always say that the best way to open up a conversation is to ask your partner their boundaries and preferences. By asking your partner what their boundaries are, it organically opens the door for them to ask you about yours or for you to just tell them.
If your partner isn’t also prioritizing your pleasure/desires/interests/fantasies, it’s time to have a conversation. Here are a few ways to bring it up:
“You know I really love when we [activity] and I’d really like it if we could incorporate more of that into our spicy time”
“I love hearing about your fantasies/desires and making them come to life. Can I tell you some of mine so we can make those happen?”
If this has really become an issue in your sex life, you are fully in the right to have a frank discussion about how you’re feeling. Here’s a way to do that:
“I want to be honest with you and tell you that when we [activity], I don’t really feel like my preferences/desires/fantasies are being prioritized. I’d really like to talk to you about how we can open that line of communication and work on this.”
Another way is to use a Yes/No/Maybe list. These lists are designed to be filled out individually and then shared with your partner(s) (or you can just fill them out to have some self-reflection about your boundaries before you enter into a partnered situation. On the list you’ll see an act, like “oral sex” and next to it, you check the yes, no, or maybe box. This allows you to see what interests match up with a partner, especially if there’s something new you want to try or if there’s something that is a hard no for you that you might not have thought of.
Move on! If it’s a casual fling or someone you aren’t that into, move along to someone else whose interests are more compatible with yours!