Couple threesome help

Hey all. Just want to get some insight into this. I'm a 21 year old woman, dating a 24 year old guy. I've been in a relationship with my boyfriend for 3 years, very happy, live together, talk about our future, all of it.

I've never been with a woman but I've thought about it before. Recently a friend of my bf- who is married to a woman- said that his wife will bring home women occasionally for them to sleep with.

I was joking about it with my bf- and he said that if I wanted to bring someone home he would be ok with it but he wasn't going to go out looking for someone.

I've been considering it, but I don't want it to complicate my relationship, as I don't know how I would feel seeing my bf- with another woman. If I did do this I think I'd want to have rules but idk if that would take the fun out of it.

Basically has anyone done this? Did you have rules in place? How did you find someone willing to do with with you and your partner? I want to explore with my bf- but do it in a way that is enjoyable for all and safe. Thanks!