A few options to consider- one is for you to sit upright, she sits on your lap facing you. (Very comfortable and user-friendly, easy to do.)
Another is for you to lay on your back with your head at the foot of the bed/couch. She stands behind you and leans over to let her breasts drape over your face. (Interesting animalistic feel to this one, sort of reminds me of the old story of Romulus and Remus.)
Then there’s my personal favorite, the ‘Patrice’ named after the late Patrice Oneal who once described it on radio. Normally you need a bed for this, but you might be able to make it work on some empty carpeted floor. You lay on your back, arms spread like a ‘T’. She lays on top of you but oriented 90 degrees to the side so that her junk is resting on one of your hands and her chest is on top of your face. In this position, both parties can mutually nurse and pleasure eachother by hand as well. (Speaks for itself. If you haven’t tried this one yet, you’re missing out on life.)