I'm not sure it's a question about "how to do it properly" (though there are certainly some ways you could try to do it that are guaranteed to fail...
). What I've found in my experience is that some women can get there, and some can't (or, at least, don't - maybe it's something that can be "learned", dunno...). Of those who can, whether the woman has larger breasts, or smaller breasts, doesn't seem to matter.
I don't claim to be any kind of expert in the "how", as far as making it happen. I do know, though, that not that long ago I had an appointment with a provider who has very sensitive breasts - I spent a large part of the appointment with my face buried in her chest, sucking on her nipples - while she had orgasm after orgasm... So, basically, we both got what we wanted out of that appointment.