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...
![Smile](http://www.eccie.net/images/smilies/smile.gif)
). 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.