My breast pattern is for reasonable sized breasts, I guess. For super-crazy-large breasts, I suppose you could use foam balls, and just wrap fabric over them.
I just made an album to show how I built my female puppet:
http://bubbleshare.com/myalbum/31625.ea8514d9a97/767703/thumbnails
I took fewer pictures during the construction than I thought I had, but here's one where you can see what it looks like with the breasts attached to the body:
http://bubbleshare.com/myalbum/31625.ea8514d9a97/767704
As far as the application goes, I glued the breasts onto the body segment, then glued the fabric over it (it involved some cutting, but as I was winging it, I don't have a pattern to share, unfortunately).
I should mention that I didn't make any nipples, but if you need them, I'd suggest either putting them on the clothes (to make the fabric covering simpler), or scuplting a little nub out of foam (or maybe use something harder, like a pencil eraser, as I imagine the fabric pressure would make it... um... smaller).