This question has been quite a few times, but what the hell.
Personally, I’ve had terrible experiences with three bi men. All have cheated or gone on to express a need for men that I couldn’t satisfy. I’m monogamous, and I expect the same. It’s impossible for me to grow a penis and give him what he wants. And I won’t be guilted into letting him play with others. Some women will be ok with that. I am not.
I guess the only tip I can give you, is that you need to be very sure that you won’t cheat, or make her feel bad about not opening up the relationship to other men. I’m sure there are bi men who are capable of that. I just haven’t dated them.