Depends on the age of the baby.
From birth to 3 months or so (it took a while for us to get the hang of side-lying nursing) DS starts out the night in the co-sleeper, and we did night nursing on the couch, sitting up (well, I was sitting up). He was waking every 4 hours or so, so if he went down at 10 pm, he'd be up at 2, and then at 6. I would be up for the day at 6, and he would usually sleep another 2-3 hours before being up for the day.
from 3 months to now: still goes down in the co-sleeper (the bottom part, we took out the bassinet once he could roll) and he comes to bed with us to nurse and sleep. Now he is going down around 9-10, and wakes, I think, around 3. (I don't always look at the clock). We nurse side lying, and I doze or sleep until he is done, the I adjust us so I am more comfortable (I like to sleep on my stomach). He might want to nurse again sometime in the night, and I just switch sides. We can nurse from both breasts on one side, but he is more up for this during the day. He usually will be up for the day around 7, but doesn't want to eat until 8 or 9.
Definitely practice during the day, with sidelying! especially in the early days, it helps if you can see what you're doing