pretty much a ditto to what kara said, except that i am VERY large busted (i was a DDD in high school- WAAAAY before thinking about kiddos).
what works best for me is when i'm out and about and sitting down on the ground, i just crossed my legs, get baby situated- my legs would support them, and i could use my hand to hold my breast, so i still would hjave a free hand to drink with or whatever. when sitting in a reguilar chair, if it it had an armrest, that would help support the child's head, if not, i would use one croseed leg to hold the body up and stil support the rbeast.
i dind't relly use a drape, as i live in the south where it isquite, and i figiured it would be cruel and unusual punishment to be under a blnket
i did however just wear larger, baggier shirts , and once the kiddo was latched on, i just let the shirt fall down to cover up everythign that the child's head wasn't.
i don't recall there being anytime when anyone got to see my nipples (that wasn't a nurse, my doula, or a good friend who wa shelping me get situated when they were tiny etc.)