I always held DD when we co-slept when she was little. Her face was always into my chest, so there was no risk of her being smothered by pillows and blankets. I would just roll her over with me when I needed to change sides. I sleep really deeply and so does DD. When she was a toddler I would occasionally wake up with a dead arm or sore neck, and from then on I would detach myself once she was sound asleep.

DD didn't co-sleep full-time as a baby, just part of each night. Some nights it would be the whole night, but when we got to the party stage at 14 mths it was either go to sleep or go back into your cot!